Visited 27.2.2010. Chepstow is a town that is rightfully proud of its medieval heritage, with an excellent castle and largely intact castellated port wall. Unfortunately, as the two sites I visited attest, it is not so good when it comes to its prehistory.
Bulwarks Camp is a small multivallate promontory fort overlooking the Wye estuary as it approaches the Severn. It's close to Chepstow railway station, making for an easy visit. Unfortunately, it now stands between light industrial units and a housing estate (this part of town is named Bulwark in recognition of the fort). It's pretty scruffy, with the northern ditch choked with vegetation and both north and south sides the scene of fair amount of fly-tipping and litter.
The small interior, as Carl says, is an open space, grassed over and lacking any obvious features. The northern and western ramparts are intact but quite low, to the south the land slopes away from the fort and on the east side is a sheer cliff.
As is often the case with these urban sites, I felt pleased that it endures, but there is no real sense of place or spirit. As I left, I did notice a sign taped to a nearby bollard asking for volunteers to come and help clear up the litter from the site, which was encouraging. But it's always sad that these places get into a mess in the first place. From here it's along the footpath south to Thornwell long barrow to see what else Chepstow does with its prehistory.