You have to know what you're getting here - there ARE campsites with amenities, near water and bathrooms, but not all of them have the amenities.  Frankly, the bare campsites are nicer - they are more spread out, wooded, and some of them are located right along the stream.  Mosquitos are something of an issue, but by no means awful; and it is a pleasure to sleep in nature with nothing but birdsong and the sound of the rushing creek.  It is close to the Savage River reservoir, which is great for kayaking.

This campground is perfect for a weekend getaway from Washington or Baltimore.  The facilities are excellent, the lake is wonderful for swimming and kayaking, and there are amazing mountain bike trails.

I stayed here for two nights with a friend, and it was serene and beautiful.  There were nice, easy hikes in or near the campsite, and the location about halfway between Philadelphia and Washington, DC, was perfect.

Another convenient hiker-biker campsite on the Towpath.  Quiet, with ample space, and river access.

This is a clean, quiet spot which is great to find after a day biking the TowPath.  It has water and a toilet, and enough flat, open area to have a decent number of socially distanced tents.

New Germany State Park is a pleasant location with a small lake for swimming and kayaking, as well as numerous trails in the wooded mountains of western Maryland. Supplies are available in Frostburg and Accident, and there are even restaurants available near Deep Creek Lake. My son and I thoroughly enjoyed a long weekend and found it conducive to relaxing and discussing his future plans.