Aug 08, 2012· Grinding Gravel Gravel Grinding in ia, Maryland, Pennsylvania and West ia. ... The first is in Round Hill (see 40 miler description). The second is the Philomont General Store at mile Loudoun Gravel Century Like it says, This route is a 100 miler with 76 miles of Gravel roads and just 24 of paved roads. The pavement is so ...