So much for cutting through Prospect Park to get to work in the morning if you are a car commuter. Starting next week and for the rest of the summer, the park is going completely car-free. East Drive was only open to cars through the weekday morning rush anyway (7-9 a.m.). That is also when you'll see a lot of runners and walkers. That is why the west side of the park closed to traffic permanently in 2015.