Puerto Rico is a Caribbean island with a difference. It has the pristine beaches, tropical climate, crystal-blue sea and coconut palms characteristic of its counterparts, but along with its unmistakable Spanish colonial heritage, the island is today part of the United States Commonwealth, meaning it has a first world infrastructure mixed in with its traditional Latin American culture. Hamburgers are as endemic as island dishes like , and freeways connect shantytowns to strips of high-rise beachfront hotels. The second thing that makes Puerto Rico different to other Caribbean holiday Meccas is that it remains largely undeveloped, except for the coastal region around its capital city, San Juan. The island is edged with some magnificent beaches featuring coral reefs, most uncommercialised and easily reached from the capital and its large resort hotels because the island is small and compact.

Exploring Puerto Rico, both around its coast and the interior, is a delight. Roads are excellent and there are numerous interesting attractions and unrivalled experiences, from the world's largest radio telescope to the magical experience of swimming at night amongst tiny phosphorescent creatures on the offshore island of Vieques.

Historically Puerto Rico, like many other Caribbean islands, was originally inhabited by Taino Indians until the arrival of Christopher Columbus and the instigation of Spanish rule and settlement. The island's capital and larger towns have preserved their Spanish heritage as 'old quarter' tourist attractions, full of charm and interest. Puerto Rico is a hybrid of old and new which makes it an intriguing destination, rather than just another tropical island paradise.

Old San Juan

Address: San Juan

This area, encompassing about seven blocks, dates back about 500 years to the Spanish occupation when it served as a military stronghold that even repulsed Sir Francis Drake. The original cobbles on the streets are blue-tinged, and were originally ballast on the Spanish ships. The ancient stones set off the more than 400 restored 16th and 17th century Spanish colonial buildings that fill Old San Juan and draw thousands of tourists to walk the narrow, steep streets every day. The old town is enclosed in amazingly thick, high walls and features numerous attractive plazas bearing sculptures and memorials.

Spanish Forts

Address: San Juan

Admission: US$3 (adults), concessions available Forts open daily 9am to 6pm.

Telephone: 729 6960

The mighty six-level fortress of San Felipe del Morro, built in 1540, towers 140 feet (43m) above the sea on San Juan Bay, its 18-foot thick (5m) walls having proved a worthy defence against invasion. The largest fortification in the Caribbean, it is a maze of tunnels, dungeons, barracks, lookouts and ramps, offering spectacular views from atop its ramparts. Also in Norzagaray Street, Old San Juan, is El Morro's partner in defending the city, Castillo San Cristobal, built in the 17th century to a confusing and intricate modular design.

La Fortaleza

Address: Fortaleza Street, Old San Juan San Juan

Admission: Free Monday to Friday, 9am to 5pm.

Telephone: 729 6960

The Fortaleza was built in 1540 as a fortress to guard the entrance to the San Juan harbour, but later became the official Governor's residence. During succeeding centuries the original structure has been remodelled and expanded, with a neoclassical façade being added in 1846 to leave the building with its palatial aspect. The current governor of Puerto Rico is in residence - the 170th Governor to live in the Fortaleza.

Saint John the Baptist Cathedral

Address: Cristo Street San Juan

Admission: Daily tours from 8.30am to 4pm. Regular services are held

Telephone: 722 0861 or 722 1709

San Juan's Cathedral was originally built in 1521 by Puerto Rico's first Spanish bishop as a thatched wooden church, but was destroyed in a hurricane in 1526. The current medieval structure, built from the stone brought in from inland quarries by horsepower, dates from 1540, although extensive renovations and reconstruction was carried out in 1917. The cathedral features Doric columns and elliptical vaults, and contains the marble tomb of the island's first governor.

La Casa Blanca

Address: San Sebastian Street, Old San Juan San Juan

Admission: US$2 (adults), US$1 (children) Tuesday to Sunday 9am to 12pm and 1pm to 4.30pm. Guided tours by appointment Tuesday to Friday

Telephone: 724 4102

The family of Puerto Rico's first governor, Ponce de Leon, whose descendants inhabited it for 250 years, built the historic homestead of Casa Blanca in 1523. It was subsequently taken over by the Spanish and then United States military. Today the mansion house contains two museums. A small section is dedicated to artefacts associated with the Taino Indians, while the rest of the house depicts the life of those who lived there through the 16th, 17th and 18th centuries.

Casa del Libro

Address: 255 Cristo Street San Juan

Admission: Free Tuesday to Saturday 11am to 4.30pm

Telephone: 723 0354

The 18th century mansion known as Casa del Libro houses a vast collection of rare sketches, illustrations, ancient manuscripts and books, some dating from before the 16th century. The museum's most prized possessions are two royal mandates signed by Ferdinand and Isabella of Spain in 1493 regarding the provisioning of Christopher Columbus's fleet for his second voyage to the New World. This was the voyage during which Puerto Rico was discovered.

University Campus

Address: Rio Piedras San Juan

Admission: Museum open Monday to Friday, 8am to 4.30pm and weekends 11am to 5pm. Gardens open daily 6am to 6pm.

Telephone: 764 0000 ext 2452 (museum); 763 4408 (gardens)

The University of Puerto Rico campus in the Rio Piedras offers two attractions for visitors. The University Museum contains archaeological and historical exhibits and holds monthly art exhibitions. The Botanical Gardens in the grounds of the University are a living laboratory displaying the native flora of Puerto Rico, containing more than 200 species of tropical and sub-tropical plants.

Museo de Arte

Address: 299 De Diego Avenue, Santurce San Juan

Admission: US$6 (adults), US$3 (children) Tuesday to Saturday 10am to 5pm, Sunday 11am to 6pm.

Telephone: 977 6277 ext. 2290

Puerto Rico's showcase art gallery opened just a few years ago at a cost of millions of dollars. The gallery is housed in a former city hospital in Santurce and offers a permanent and visiting exhibition. The aim is to highlight the island's heritage through the work of local artists, such as Francisco Oller, who studied in France with Cézanne, and Jose Campeche, a late 18th century Classical painter. The museum has been described as a 'living textbook of Puerto Rico', spanning the centuries through the medium of art.

Arecibo Ionospheric Observatory

Address: Arecibo San Juan

Admission: $6 (adults); $4 (children) Open daily from 9am to 4pm in June, July, December and January. Closed on Mondays and Tuesdays in the remaining months

Telephone: 878 2612

America's ears and eyes are focused on the stars from the island of Puerto Rico. In the northwest mountains of the island about 90 minutes drive west of San Juan, among the Karst Country hills, is one of the most important astronomical research facilities on earth, the Arecibo Ionospheric Observatory. Its massive dish is larger in area than a dozen football fields and is sited in a sinkhole, aimed at the heavens and tuned to detect the slightest sounds emitted from the farthest stars. This is the home base for NASA's 'SETI' (Search for Extra-Terrestrial Intelligence) project and as such holds great fascination for visitors. A Visitors Centre is equipped with interactive exhibits to demonstrate how the huge structure works. Visitors can hike to the viewing platform to view the vast tiled dish.

Rio Camuy Cave Park

Address: Route 129 San Juan

Admission: US$12 (adults), US$7 (children) Wednesday to Sunday 8am to 3.30pm; closed when raining

Telephone: 898 3100

Well worth a day trip from San Juan is the incredible 268-acre Rio Camuy Cave Park, two hours south-west of the city. The park is the site of miles of subterranean caverns that were carved out of the limestone by the Camuy River more than a million years ago. Only seven miles (11km) of the caves have yet been fully explored, but 16 entrances have been discovered to what is believed to be the world's largest cave network. Well-maintained walking trails lead visitors down 200 feet (61m) into a fern-filled ravine to explore the cathedral-like caverns. Guided tours are available through one cave and two sinkholes, where you will see stalactites, stalagmites and plenty of bats. The caverns also contain a unique species of blindfish. The park has picnic areas, walking trails, food outlets, an exhibition hall and a souvenir shop.

Caribbean National Forest (El Yunque)

Address: Fajardo

Admission: Daily 7.30am to 6pm. El Porto Rain Forest Center: 9am to 4.30pm

Telephone: 888 1880

The Caribbean National Forest, 35 miles (56km) east of San Juan, is the only tropical rainforest in the United States National Park system and was named El Yunque by the Spanish. Its 28,000 acres contain about 240 different species of tree and numerous other plants from tiny wild orchids to giant ferns. Visitors can start their visit at the El Portal Tropical Forest Centre where there are films, exhibits and interactive displays on the rainforest. Maps are available and you can choose from dozens of walking trails through the forest, graded according to difficulty. Nearby is Puerto Rico's best beach, Luquillo Beach, with its soft white sand and coconut palms.

Las Cabezas de San Juan Nature Reserve

Address: Fajardo

Admission: US$7 (adults), US$4 (children) Wednesday to Sunday, reservations required. English language tours 2pm.

Telephone: 722 5882 (weekday reservations), 860 2560 (weekend reservations)

Located on three promontories on the extreme northeast corner of the island, Las Cabezas reserve is one of the most beautiful and bio-diverse natural areas in Puerto Rico. The reserve is close to Fajardo, a major marina and diving resort, about an hour's drive from San Juan. The area offers pristine beaches ideal for snorkelling. The reserve contains seven different ecological systems including coral reefs, sandy beaches, lagoons, mangroves and dry forest. It is also home to several endangered species. Boardwalk trails provide easy access. A restored 19th century lighthouse, El Faro, is situated on one of the headlands and offers an information centre and observation deck.

Parque de Bombas Fire Station

Address: Plaza Las Delicias Ponce

Admission: 9.30am to 6pm (closed Tuesdays).

Telephone: 284 4141, extension 342

A unique attraction on the central Plaza de las Delicias is the unusual Ponce fire station, a landmark wooden building painted in black and red stripes. The firehouse was built in 1882 and was tested to its limits just a year later when the city experienced a massive fire. Firemen from the Parque de Bombas station heroically battled the blaze. The station remained headquarters for the fire fighters until 1990, when it was turned into a museum open to the public.

Ponce Art Museum

Address: 2325 Avenue Las Americas Ponce

Admission: US$5 (adults), US$2.50 (children under 12). Monday to Friday 11am to 7pm, Saturday to 8pm, Sunday to 5pm.

Telephone: 200 7090

The 'Museo de Arte de Ponce' contains the largest art collection in the Caribbean, housed in a building designed by Edward Durrell Stone, who designed the Museum of Modern Art in New York. The impressive building is comprised of seven interconnected hexagons topped with glass cupolas. Inside are more than 1,000 paintings and 400 sculptures covering classical, ancient and contemporary works. Among the prizes of the collection are works by Velasquez, Rubens and Rodin. Puerto Rican art also features strongly.

Coffin Island

Address: Ponce

At weekends a ferry carries visitors from the pier at La Guancha on the Ponce waterfront to Coffin Island, a tiny uninhabited island five miles south of the city, where there are pristine beaches and a marked snorkelling trail. Visitors can also explore the 19th century Caja de Muerto Lighthouse that has been restored and houses a museum.

Museum of Puerto Rico Music

Address: 50 Isabel Street Ponce

Admission: Wednesday to Sunday 9am to 5.30pm.

Telephone: 844 9722

This museum is dedicated to documenting the rich tapestry of the island's music history and pays tribute to Puerto Rican musicians. It explains the significance of the romantic danza music style, and the African-inspired popular forms of bomba and plenza. The museum features displays of Indian, Spanish and African musical instruments, and memorabilia of local composers and performers, housed in the attractive former residence of the Serralles family, renowned rum producers.

Castillo Serralles

Address: 17 El Vigia Ponce

Admission: US$9 (adults), US$4 (children under 16) 9.30am to 5pm (closed Mondays).

Telephone: 259 1774

Perched above the city on El Vigia Hill is the restored residence of the Serralles rum-producing family. The multi-level Spanish-revival hacienda, designed by Pedro de Castro, is a beautiful example of the island's 1920/30s architecture. The house surrounds an elegant courtyard featuring fountains and is renowned for its splendid carved dining-room ceiling. The mansion is set in magnificent terraced formal gardens.

Tibes Indigenous Ceremonial Center

Address: Ponce

Admission: US$2 (adults) Open Tuesday to Sunday 9am to 4pm

Telephone: 840 2255

This ancient Indian site, still being excavated, is one of the most important archaeological sites in the West Indies. Apart from an ancient cemetery, it also features the remains of seven courts used by the Igneri (pre-Taino) people for a football-like game, two dance grounds, and standing stones believed to have been used as an ancient astronomical observatory. A popular tourist attraction, just two miles (3km) north of Ponce, the site has been equipped with a reconstructed Taino village, a museum, exhibition hall, café and souvenir shop. Visitors are taken on conducted tours.

Culebra and Vieques

Address: Fajardo

Telephone: 863-0705 (for current departures to Culebra and Vieques)

Dubbed 'the enchanted isles' Vieques and her smaller sister Culebra lie off of Puerto Rico's east coast, accessible from San Juan by air and from Fajardo by ferry. Both support a few thousand friendly, laid-back inhabitants who live life peacefully and slowly, enriching rather than impacting on the natural beauty of their home. Vieques is 20-odd miles long and five wide and consists largely of the biggest wildlife sanctuary in the Caribbean, protected by the United States Fish & Wildlife Service. Some of the world's most beautiful beaches, with azure clear waters and sugary white sand, are to be found in the sanctuary. If you plan to visit Vieques stay overnight to experience its premier attraction, Bio Bay. On a moonless night the bay glows with the bioluminescence radiated by a microscopic one-celled organism called a dinoflagellate, providing an unforgettable sight. Smaller Culebra, just seven miles long and three wide, is a few miles north of Vieques and is renowned for the clarity of the waters washing its shores. This is occasioned by the fact that the island has no rivers or streams causing run-off: the arid island has to have water piped from Puerto Rico via Vieques. This quiet, unspoiled island offers unrivalled snorkelling and scuba diving in its magnificent encircling reefs, kayak expeditions and hiking trails for bird-watchers through the Culebra National Wildlife Refuge.

Luis Muñoz Rivera Park

Address: Between aves. Muñoz Rivera and Ponce de León San Juan

Admission: Free Open daily

Telephone: 787 721 6133

Named in honour of Puerto Rican statesman Luis Muñoz Rivera, and featuring plenty of wide open space, picnic areas, walkways and even a small children's playground, the Luis Muñoz Rivera Park is the perfect place to take the kids for a day of fun in the sun, especially those who have been cooped up on board a cruise ship. Pack a picnic or simply enjoy the fresh air and scenery along the tree-lined paths, decorated artistically with art and mosaics.

Camuy River Cave Park

Address: Arecibo San Juan

Admission: Open Wednesday to Sunday from 8:30am to 4pm. Last tour departs 3:30pm

Telephone: (787) 898 3100

Children will feel like they are in an Indiana Jones movie when they visit the magnificent Parque de las Cavernas del Río Camuy (Camuy River Cave Park), a large network of natural limestone caves and waterways which can be explored by trolley. The caverns and underground tunnels were created over a million years ago by the tropical Río Camuy (Camuy River) which is the third longest underground river in the world and is home to a unique species of fish that is totally blind. Only three crater-like sink holes and two caves are open to the public which are reached by a guided trolley that descends into a sinkhole lined with dense tropical vegetation. Kids will love the spacious grounds of the park, which include a cafeteria, picnic area, gift shop, walking trails, exhibition hall, and theatre.

Golf

A links-lover's paradise, Puerto Rico is home to more than 20 golf courses, of which almost all could be considered championship-level courses. Puerto Rico's luxury resorts offer some of the best golf courses on the island. The Westin Río Mar Beach Resort and Country Club near San Juan features two world-class oceanside courses. Northwest of San Juan is the Hyatt Regency Cerromar Beach Resort & Casino and Hyatt Dorado Beach Resort & Casino featuring four Robert Trent Jones Sr. designed courses and arguably the best golfing to be found on the island. The Wyndham El Conquistador Resort and Country Club and the Palmas Del Mar Resort & Villas in Humacao also offer two of the most breathtaking courses in the Caribbean.

Scuba diving

Scuba diving and snorkelling, for beginners and experts alike, is the reason why Puerto Rico is often called the Caribbean's best kept underwater secret. Off the southwest coast, from the village of La Parguera to the city of Ponce, lie some of the island's most extraordinary dive sites, including the Black Wall, home of the Caribbean's rarely seen black coral. Another noteworthy spot is Isla Mona, off the west coast of Puerto Rico, known as the Galapagos of the Caribbean. It is home to sea turtles, dolphins and various species of rare marine life. Scuba Diving Magazine readers voted Puerto Rico one of the top five destinations for shore diving in 2006, and the island was in the top 20 for overall diving. For visitors looking to get close to the water, but not necessarily submerged in it, Puerto Rico offers various other water sports such as world-class surfing, windsurfing, sailing, kayaking and deep-sea fishing.

Cruising in San Juan

San Juan is more than just the capital of Puerto Rico, it's the very centre of the Caribbean cruise scene. Over 1 million passengers begin or end their cruise here and some of the biggest luxury liners base themselves at the harbour. That's great news for passengers because San Juan is a wonderful city to see and explore. It's friendly, safe, surprisingly good value, and jam-packed with historical sites. The main attractions are in Old San Juan which is located not far from the main disembarkation piers. The area is an historical wonderland of Spanish colonial architecture, spread out over 7 blocks of cobble-stoned streets – the same stones that served as ballast for ships 500 hundred years ago. Key sites are San Felipe del Maro, the largest fortification in the Caribbean and sentinel to the Spanish Armada, formerly based in the port below, and La Fortaleza, built in 1540 as the Governor's residence (the current governor is the 170th to live there). For a more modern twist on the city don't miss the San Sebastian street festival from 17 to 20 January when the city really comes to life.Hungry? Head over to La Mallorquina on Calle Cruz, the most famous purveyor of Puerto Rican food in the country. The waiters may be as old as the building, but the food is excellent and truly authentic. Nearby La Barrachina claims to be the birthplace of the piña colada.Shoppers can head to Cristo Street where there are abundant factory stores and idiosyncratic souvenir joints. Good news for American shoppers is that since Puerto Rico is part of the USA, purchases are duty-free, a fact that many rum-laden passengers exploit to the full.Those with time on their hands might head out of the city to see Arecibo Observatory. Its enormous dish – the size of 12 football fields – help make this the most significant astronomical observatory in the planet. A little further afield, at 2 hours drive from San Juan, is the 260-acre Camuy Cave Park. Although still being discovered this subterranean wonderland is already deemed the largest cave network in the world. Cruise passengers can visit the La Casita tourist information centre just off Pier 1 on Calle Marina to plan their exploration and excursions.

Aguaviva

Address: 364 Calle Fortaleza San Juan

Food Type: Seafood

Aguaviva's cool, turquoise décor is very laid-back, in stark contrast to its chaotic atmosphere. The stained-glass aquaviva (jellyfish) replicas are intriguing, best contemplated over oysters and a stiff drink from the bar. An open kitchen serves delectable cuisine including a marlin and garlic ceviche (appetiser), and a seafood tower made up of fried oysters, coco-flavoured shrimp and fried octopus. The grilled mahi-mahi with smoky shrimp, salsa and yucca is also fantastic, as is the paella with seafood and pork sausage. Reservations required.

Augusto's Cuisine

Address: 801 Ponce de León Ave San Juan

Food Type: French

This elegant and glamorous restaurant flaunts its European flair in a portentous grey and green dining room within the Hotel Excelsior, Miramar. Fresh ingredients are used to create indulgent offerings such as creamy corn and oyster soup, an exquisite lobster risotto or medallions of veal with foie gras and Madeira sauce. The wine list is also outstanding.

Dragonfly

Address: 364 Calle Fortaleza San Juan

Food Type: International

Dragonfly's décor is reminiscent of an old San Francisco bordello with beaded curtains, fringed lamps and gilded mirrors. Their trademark drink is the 'Dragon Punch', often accompanied by live Latin jazz performances. The plantain chips, chicharrónes (pork rinds) and spicy crab cakes are easily followed by delicious red snapper or grouper, while the pumpkin and bean selection is quite formidable. For those with bigger appetites, the barbecued lamb shank is a must! Reservations required.

Parrot Club

Address: 363 Calle Fortaleza San Juan

Food Type: Caribbean

The Parrot Club is found in a stately 1902 building and occasionally hosts local dignitaries in its ambient dining hall. The courtyard tables are accompanied by live music among potted ferns, orchids and palms. This bistro and bar blends Puerto Rican cuisine with Spanish, African and Taíno flavours. Halibut, salmon and mahi-mahi form part of the ceviche (appetiser) menu and the criolla-style flank steak is superb for a main course, as is the tuna with rum and orange-essence sauce. A favoured drink is their trademark 'Parrot Passion'. Closed for two weeks in September.