A hiking tour of the spectacular Gran Desierto sea of dunes with expert guides. Visit North America's only true sand sea to learn about dune geography and the unique adaptations of its inhabitants, as well as the geologic processes involved in the formation of the basin and range geologic province. This 5-hour trip involves two hours of walking to and from the dunes.

Photo: Hem Nalini Morzaria Luna

To all these ecotours you should bring: water, munchy snacks, hat, sunscreen, binoculars, camera. On the Kayak Capers, Estero Excursion and Tidepool Explorations you can count on getting your feet wet - at the very least. So wear shoes and clothes that you don't mind getting wet. For the Dunes and Pinacate trips, good walking shoes are in order. The Dunes trip involves a long but not strenuous walk. The Pinacate trip requires more driving but in both excursions there will be ample time to explore on foot these spectacular natural settings.