Reston is also relatively close to Washington, DC. There are several things to do in the city. If you stay a bit longer, you can check out the Smithsonian Museums (which are free!), the monuments, and fun neighborhoods. There is a metro stop in Reston that goes straight into Washington, DC.
Leesburg is a town close to the wedding site. It's a small (very small) town in Virginia that makes up for it's small size with its large charm.