Potomac Blockade Boat Tour is at 10 a.m. May 19 at Leesylvania State Park, 2001 Daniel K. Ludwig Drive, Woodbridge. Cruise the Potomac River shoreline and view sites that were critical to the Confederate forces’ successful blockade of Washington D.C. from September 1861 to March 1862. Tour includes lunch. The cost is $30 per person; reservations are required. Call 703-792-4757 to make reservations. less