Riffa is not walkable in the conventional sense — it is a sprawling residential city built around the car. Taxis and ride-share apps (Careem and Uber both operate in Bahrain) are the practical way to get around. The city is about 15 kilometres south of Manama via the main highway, and taxis between the two run frequently and are reasonably priced.
The Bahrain International Circuit at Sakhir is a further 10 kilometres south of Riffa. During Grand Prix weekend a shuttle service operates from Manama; at other times a taxi is the only option unless you have a rental car.