Distributed vehicle route planning

Techniques are described for controlling and/or influencing the routes driven by vehicles in a fleet of vehicles managed by a fleet routing system. The fleet routing system may determine route data for vehicles to perform requested driving trips based on the current and previous driving trips performed by the fleet. For example, the fleet routing system may evaluate the current driving trips being performed by the fleet to determine modified destinations for driving trip requests. The fleet routing system also may modify various route data, map data, traffic data, and the like, including determining additional waypoints, restricted driving regions, and/or distributed driving regions, to influence the vehicles in the fleet to determine driving routes to prevent congestion on roads and at crowded pullover locations, and to improve vehicle safety, efficiency, and traffic distribution.