Dominica - an english-speaking Windward Island not to be confused with the Dominican Republic - is a naturalist's heaven. The rugged, unspoiled landscape of mountain peaks and valleys is covered with lush rain forests, impressive waterfalls and exotic flora. Accordingly, hiking, mountain climbing and exploring are popular visitor pastimes. Although most of the beaches are not the white sandy variety of other caribbean destinations, scuba diving is great around the coral reefs and shipwrecks, and inland rivers offer wonderful swimming.

Welcome to Dominica, an island truly unique in its lushness and natural beauty. Its mountains are the highest in the Caribbean; its evergreen oceanic rainforest is one of the last in the world.

Visit Cabrits National Park, which lies on the northwest coast and covers 1,313 acres, including over a thousand acres of marine area. The Park includes the peninsula above Portsmouth, which provided defense for the port during the 18th century. Explore the impressive ruins of Fort Shirley, which was constructed of local volcanic stone and once housed 600 men. The area has been admirably restored and affords a spectacular view of the bay. Also near the Park are the dramatic swamp lands and luscious vegetation along the Indian River. The beach at Prince Rupert Bay, shaded by seagrape and coconut palms, is great for a picnic and snorkeling.

Morne Diablotins, the island's highest peak and the source of many of its rivers, rises in the Northern Forest Reserve. In this area are found the Sisserou and Jaco, Dominica's indigenous parrots. Hiking and parrot watching are favorite activities. A climb up the Morne, beginning near the coastal town of Dublane, will allow you to see all the types of vegetation on the island, from the scrub woodland of the coast, through the rain forest, to the elfin woodland near the peak.The Reserve is a large area with rough terrain. A guide is recommended.

In the northeast is the 3,700 acre Caribe Territory, which is home to descendants of the island's original inhabitants-the Carib Indians. Although mainly agriculturists, they still produce baskets, canoes and other traditional items. The Catholic Church at Salybia has an altar fashioned from a dugout canoe. Craft shops throughout the Territory offer beautiful examples of the Caribs' wares.

The rainforest in Morne Trois Pitons National Park, in the south central portion of the island, contains plant life that will amaze you-from giant ferns and hanging orchids to sweet-smelling wild ginger. There are six established hiking trails. Within the Park are Boeri Lake and Freshwater Lake, both accessible on foot from Laudat Village Road. Harder to reach is Boiling Lake, a difficult hike of about four miles. If you undertake the hike, you'll be rewarded with sights of the Valley of Desolation,Titou Gorge and the Valley of the Breakfast River. A guide is strongly suggested for the trip.

Among the other popular sites are the spectacular Trafalgar Falls where you can bathe in the rocky pools at the foot of the mother falls. Caution is advised on the slippery rocks bordering the pools. Emerald Pool, off Castle Bruce Road, is one of the most easily accessed. The trail leading to this grotto is lined with examples of Dominica's beautiful flora.

To view historic Dominica, stroll through Roseau and see the island's architecture-with wooden buildings ornamented with fretwork or ''gingerbread,'' balconies and jalousies. Many of the restored older buildings are built of thick masonry walls. The Catholic Cathedral and Anglican Church are well worth a visit. The Old Market Square is behind the Post Office and has seen slave auctions and executions as well as the sale of produce. It is currently a craft market. On Saturday you must see the new market at the mouth of the Roseau River, one of the Caribbean's most colorful, with the bounty of Dominica's fruits and vegetables on display. The Botanical Gardens were originally designed as an experimental facility to advance agriculture, but ornamental plants can be seen here, too.

Dominica underwater is as spectacular as above. The unexplored coral reefs, dramatic drop-offs and wrecks offer spectacular world class diving possibilities. At Soufriere try a dive known as ''Champagne'' for the bubbling waters created by volcanic activity on the sea bed. In Douglas Bay in the marine portion of Cabrits National Park there are underwater snorkeling trails.