Fort Williams is a hugely popular tourist destination in Cape Elizabeth, Maine. Part of the draw is the fact that it is free admission. An even bigger draw is the large open fields for picnics and fun. Probably the greatest draw is Portland Head Light - Maine's oldest and most famous lighthouse, and probably the most frequently painted and photographed lighthouse in the world.
Portland Head Light
There is a short walking/hiking trail that stretches along the coast from the lighthouse, which provides beautiful views of the ocean, the rocky coast, and the lighthouse itself.
Laura and I went for a walk along this cliff trail last summer. The walk is not difficult; the trail is well maintained and easily traveled by my wife, who was seven months pregnant!