The best area to stay in Tonantins is the central riverside district, particularly around the main square, Praça de Tonantins.
This area is the heart of the town, where most of the limited amenities and guesthouses are located. It's a compact district, easily navigable on foot, with the main street, Avenida Solimões, running parallel to the river. You'll find the local market, a few eateries, and the port where riverboats dock, all within a short stroll.
For travellers looking for convenience and a central base from which to explore the surrounding Amazon, this area is ideal. It provides direct access to the river, which is the primary mode of transport and the gateway to any excursions.