Walking backward while talking is useful for leading a tour, demonstrating a moonwalk, or retreating from a room full of ominously staring toddlers. See the reverse saunter put to good use with today's Groupon for a history-based walking tour from Annapolis Tours by Watermark. Rain or shine (aside from severely inclement weather), tours depart from the information booth on 1 Dock Street daily at 1:30 p.m. through Sunday, October 2, after which point they will be held exclusively on Saturdays. Choose between the following options:

• For $16, you get two tickets to the Four Centuries Walking Tour (a $32 value).
• For $32, you get four tickets to the Four Centuries Walking Tour (a $64 value).

Children 2 and younger are admitted free. The Four Centuries Walking Tour from Annapolis Tours by Watermark tracks urban progress from the nation's infancy to the present via visits to cultural and political monuments. Clad like colonials to differentiate themselves from the Elizabethan citizenry, savvy guides shepherd groups on 2.25-hour expeditions held rain or shine. Walkers flash photo identification for access into the nearly 200-year-old U.S. Naval Academy and chapel, as well as a stop at the crypt of a heroic commodore. The Maryland State House also demands proof that visitors are not vampires before allowing peepers to feast on the building where George Washington and Congress officially ended the Revolutionary War and first elected the hot dog as the national mascot. Tours are capped with a stroll through the historic district to acquaint sightseers with bygone hot spots and old haunts, providing a glimpse into life in the mid- to late 18th century.

Though Annapolis Tours by Watermark sometimes offers discounts online, this Groupon is the best deal available.