Iguana Mama (Calle Principal, tel. 809/571-0908, www.iguanamama.com) is the best ecotour operator in the Dominican Republic. It has been around for a while and has a great selection of exhilarating tours and excursions, like hiking, trekking, canyoning, and cascading, as well as some more laid-back choices like catamaran rides. But Iguana Mama is best known for its mountain-biking trips (starting at US$65), from one-day to multiday biking excursions that take you deep into the Dominican Republic that few other tourists see. Some trips even go across the entire country! ¡Muy Dificil!

Hiking and mule trips to Pico Duarte are a good choice through this company as well (US$450). Waterfall tours are all the rage in extreme tourism, and Iguana Mama has set up a spectrum of options from the 27 Waterfalls (US$79) to the aptly named Super Big Bastard (US$149), where you will need some prior knowledge of canyoning and some swimming prowess (and a reasonable amount of cojones).

Browse the website or stop by the office to look at brochures to get a feel for the limitless possibilities available to you; if you don’t see just the right excursion, they will customize one for you. Among the top 10 reasons to choose Iguana Mama as your tour operator is that they run a truly sustainable and responsible tourism company by keeping an eye on the community they are in and not running rampant over it without giving back. We love that.

Tours, Trips, Treks & Travel (Cabarete, tel. 809/867-8884, www.4tdomrep.com) offers excursions that are adventure based and educational, ranging from photography safaris throughout the country to Santo Domingo museum tours to deep-sea fishing or golf excursions.

Cabarete Nature Park & Caves (Callejon de la Loma, tel. 829/201-4363, 9 a.m.–4 p.m. daily, US$15/ adults, kids half price). Take your bathing suit when you take a 90-minute tour with an expert guide through a protected area where you will learn about trees and medicinal plants, fauna, and the Taíno Indians and explore the Crystal Cave, because you will be able to swim in the frigid water of the cave 25 meters below the surface. Tours are given in English, Spanish, German, or French. You cannot visit this site without a tour guide. Although the walk is a pleasant and easy one for elderly and children, the cave swim is a different story because of the frigid temperature, about 23°C (73°F).