If on one hand the sidewalks are not very accessible, much of the tourist region of Rio is flat and walking around the city is a good way to explore it and feel the atmosphere.
Most sidewalks are built with portuguese pavement that form beautiful mosaics, but are also difficult to maintain. Watch out for potholes and bumps along the way and be advised the pavement gets really slippery when wet. Your best bet is to avoid wheelchairs with very small or thin wheels. The larger and wider, the better! If you have a Freewheel, bring it to Rio. It’ll make getting around a lot more comfort!
In the neighborhoods of Rio’s South Zone (Copacabana, Ipanema, Leblon etc.), you will find ramps in almost all the sidewalks. Some of the ramps are not very good, but the Cariocas (Rio’s natives) are always willing to help. Do not hesitate to ask for help! In neighborhoods like downtown and Lapa, wheelchair access is worse, but has improved steadily in recent years.
Some suggestions for walking tours around the city, all quite accessible:
Back in Lagoa Rodrigo de Freitas (7 Km)
Boardwalk Copacabana (4 Km)
Boardwalk Ipanema (3.6 Km)
Av. Rio Branco (1 Km)
Pista Claudio Coutinho (2.8km)