The cache is not accessible from Md Route 2 or Md Route 100. The closest parking that I'm sure of is at Marley Station Mall. See waypoint. There is however parking further south near the LA Fitness.
This cache is only accessable from the B&A Trail. It is not in the park, but since the access is, this cache is not available 24/7. The Park hours are Dawn to Dusk. Please respect that.
You are looking for a 35mm type container at the base of a large standing tree.
There is a small trail that leads from the paved trail into the wood line at the sharp turn in the paved trail. I followed this trail passed where I hid the cache about 300 feet and there was what seemed to be a homeless tent down there. So you probably don't want to continue too much further than the cache placement. Be careful that muggles don't see you enter the woods here, it would just look odd.
Happy Trails.