The community of Baltimore, just after Refugio Amazonas lodge, is the only real settlement on the river, and has a few simple hospedajes (homestays). Baltimore is accessible by taking a Laberinto-bound bus from Puerto Maldonado and getting off at Km 37. From there, a footpath goes to Baltimore (about three hours). No public transport exists to points further upriver.
You can also reach Baltimore by the snail-paced weekly public boat.