First Landing State Park in Va Beach is great. Isolated campsites with plenty of privacy and then you have the bike path on the beach front (it can get VERY crowded on the weekends). You'll find kids of all ages from 3 to 93 riding along the boardwalk bike path. I absolutely love riding in the area (it's the bikinis for me). There are also many bike paths in that general area of the campground. You can ride from the campsites to the boardwalk but it's a ways for the little ones.