Among the main Canary Islands, El Hierro and La Gomera are widely considered the least touristy. El Hierro, the smallest and farthest south, is a UNESCO World Biosphere Reserve that focuses on sustainable tourism rather than large resorts; it is perfect for those seeking volcanic landscapes and quiet diving spots. La Palma (known as "La Isla Bonita") is another excellent choice for avoiding crowds, as its steep terrain and black sand beaches have prevented the development of massive hotel complexes seen in Tenerife or Gran Canaria. La Palma is instead famous for its world-class stargazing and "offbeat" hiking trails. If you want the absolute most secluded experience, the tiny island of La Graciosa (off the coast of Lanzarote) has no paved roads and very few visitors.