I've discovered that many people unfamiliar with Prospect Park are astounded when they see the extent of the unleashed dog problem. Below is a map that I created by combining the official Prospect Park map with a Google Earth satellite image of the park. I think that it gives a fairly good impression of how the wooded areas crisscross all the open meadows. It also clearly shows the impossibility of containing unleashed dogs and the huge percentage of the park's area that they monopolize.
Prospect Park with satellite image overlay (click to enlarge)
The unofficial "courtesy hours" permit unleashed dogs on the Long Meadow and the Peninsula Meadow from 9pm to 9am and the Nethermead Meadow from 5pm to 9am. What's wrong with this picture?!