Usually, you'll find Mount Rinjani trekking at the top of nearly everybody's list of what to do on Lombok, and rightly so! Trekking Mount Rinjani was hands down one of the most epic adventures we had on Lombok. In fact, I believe that climbing Rinjani is one of the most incredible hiking experiences you can have in South East Asia. The volcanic rim is breathtaking and the spectacular views of the crater lake makes you feel like you're on another planet! Most treks leave from Senaru, however, less-popular routes are also completed from Tete Batu and Sembalun. If you're chasing the summit, I'd suggest trying to negotiate with local trekking guides in Senaru or in Sembalun.
National Park is literally the domain of living dragons, Indonesia’s apex super-predators. Rinca Island (just east of Komodo) – smaller but more densely populated with particularly aggressive dragons – is one of the most exciting predator territories on the planet in which to trek. It is possible to combine dragons and orangutans in a single tour taking in some of the natural icons of the world’s second richest wildlife zones (only the Amazon has greater natural diversity than Indonesia).
Due to a strange quirk of geology, the three sister-lakes of Kelimutu in the center of Flores Island, are capable of dramatically changing color over the course of just a couple of days. Local people carefully watch the color transitions of the lake known as Tiwi Ata Mbupu since it is said to be the resting place of demons and the spirits of witches. It is best to stay overnight in the village of Moni where there are several homestays and hotels (as well as a lovely hot spring) so that you are on the spot to visit the crater lakes around dawn before the mountain mists descend.
The island of Sumba remains almost unknown despite being twice the size of Bali. A unique culture based on ancestor-worship has spawned a dramatic megalithic culture where giant tombstones (the largest vastly outweighing the biggest stone at Stonehenge) are moved several kilometers overland by hundreds of laborers. Home also to the ritual (and still occasionally fatal) horseback battles known as the Pasola, Sumba is one of Indonesia’s developing frontiers for adventurous travelers.