We took a trip up the river, leaving Friday night/Saturday morning at 3am (we moved our hammocks into the boat beforehand and slept on it Friday) arriving in the 3rd largest "city" in Amazonas at 7:30am. I expected a city,but found a small town with a population of about 4,000 people. We visited various locals; an artisans' shop, pink dolphins, another craft shop, then lunch. After more shopping we went to an indigenous community down river in the rain.
On Sunday, we awoke to a stunning little beach and the sweetest community of all. We went for a long trek in the jungle, where we were shown many medicinal plants, including a viagra tree and a tree that has water in it. Afterwards, the lunch was by far the best I've had in Brazil, and we were the first group to be hosted. The community is hoping to develop a tourist trade and I highly recommend it. We bought some beads and got our faces painted, then hung out on the beach until it was time to float home to Tumbira.