Our four day discovery trek with Ando was one of the best things we did throughout our whole month traveling in Indonesia! Would give 10/5 stars if possible. Absolutely a true adventure off the beaten path. Our guides Ando and Ari were so knowledgeable and professional. We felt so safe and taken care of as they guided us through a path Ari literally cut through the jungle in front of our eyes. Exceeded our expectations of getting out into wilderness and seeing real wildlife in a sustainable way. We learned so much from Ando about the orangutans, other primates, and birds of the region. Ari provided us with a local method of keeping leeches off of our clothes and skin (using tobacco water to soak our shoes and socks!), but be prepared to potentially ditch your shoes or have them cleaned after the hike, as they retain the smell and color :) Saw wild orangutan mother and baby pair on our day 1 lunch break! Tour is structured such that even if we had not seen wild orangutans on our first day, we would have had our fill of sightings on the final day, as we finished the trek through Gunung Leuser National Park, where many wild species have groups of animals that are more habituated to humans, including orangutans, macaques, and gibbons. We loved the river rafting back to Green Hill from the park, it was the perfect way to finish our trip.For our three days and nights deeper in the jungle, we did not come across another group and enjoyed peaceful evenings at our riverside campsites. Our chef, Emmanuel, prepared the most delicious food! Each meal was different and was always followed by a beautiful spread of fresh local fruit. We were always delighted and surprised by dinner, which was immensely flavorful, filling, and plant based! We ate at many great, well known restaurants during our trip through Indonesia, and yet some of our top favorite meals were homemade and cooked in the jungle on our Green Hill Discovery Trek.The trekking at times was difficult and quite steep, but the beauty and being out in the remote wilderness was so worth it. I would highly recommend this 4 Day Discovery Trek to experienced hikers that want to see areas of Sumatra most visitors would not experience otherwise. However, be advised that because Green Hill does not engage in the unsustainable practices of wildlife feeding, no sightings are guaranteed. This makes what you are able to see all the more special :)