Iquitos has no car traffic in the conventional sense — the city is not connected by road to the rest of Peru, so there are no through vehicles. Local transport is dominated by mototaxis (motorbikes with an enclosed three-wheeled cab) and motorcycle rickshaws. These are inexpensive and easy to flag down anywhere in the city; agree on a price before getting in.
The city centre and the Malecón are walkable. For the airport, mototaxis and taxis are available; the ride takes about 15 minutes and should cost under US$5. For Lake Quistococha and other sites south of the city, shared taxis and mototaxis are the practical option.