Didn't make it the whole way to Washington Monument just due to timing. The hike up Bartman Hill Trail is on the steeper side and there was a stream coming down the trail. Once on the AT the trail is mostly flat with only slight elevation gain. We saw a copperhead and a black rat snake on the trail. Some sections of the trail were quite muddy, but easy enough to walk through or on the side off without getting off trail. There are bathrooms near the lake. Entrance fee for the park is $5/person if you are out of state, and I think $3/person if you are in state.