Built in 1998 at a cost of nearly $8 million, thea href="http://www.chesapeakeinspired.com/index.php/out-about/boating/1308-tending-the-bridge"; target="_blank" Knapps Narrows drawbridge /aon Tilghman Island replaced an older bridge that was dismantled and moved 20 miles north to St. Michaels, where it now serves as a dramatic entryway to the Chesapeake Bay Maritime Museum. It's hard to believe a tiny 3-mile Maryland island in the Chesapeake Bay is home to the busiest drawbridge in the nation, but it's true, according to some reports.