I have ridden this route a few times. It can take anywhere from 3.5 to 5.5 hours depending on your pace, stops for food, and nature calls. It goes from Baltimore County to Wrightsville PA and back down to Northern Baltimore County. This is part one of two. The second will be posted shortly.
This is a short ride of only about 35 miles, but plan for 90 minutes. There are several sections of gravel and dirt as well as two stream crossings, so plan on getting your wheels dirty and your feet wet. The Clarksburg Market is a good place to start and end since they have gas, food and drink. They have a grill in the back of the store where they make a pretty good steak and cheese sandwich.