Mountain biking is one of the fastest growing sports in the country, and as more people are opting to ride their bikes on dirt - an increase in trail access is occurring. Maryland has one of the most diverse riding areas on the east coast, the state has everything from beginner flat trails, to black diamond rocky downhill runs. Whatever your skill level, you can find something near Baltimore to challenge your riding capabilities!  Patapsco Valley State Park  One of the most popular areas in Maryland - and for good…