Before there was Mapquest.com, there were people who blazed their own trails. Two of those were the famed Meriwether Lewis and William Clark, who 200 years ago journeyed from East to West and back again. In 1807 or '08, Nicholas King, cartographer to President Jefferson's War Department, mapped the expedition, using Clark's routes, Lewis's observations, and information supplied by Native Americans. (Clark made one map in 1805 and published another in 1814, with the history of the expedition.)
The King map is in the permanent collection of the Boston Athenaeum but is so fragile it's not displayed. In time for the ongoing hoopla surrounding the Lewis & Clark bicentennial, the Athenaeum and Boston's Haley & Steele Gallery have drawn up limited-edition facsimiles. At $385 for the ''Anniversary Edition" (400 copies made) and $850 for the ''Deluxe Folded Facsimile Edition" (350 copies), you might head for Mapquest when finding your own way to the Pacific Ocean -- but then you wouldn't get a stamped and numbered version with the Athenaeum's certificate of authenticity.
Maps available at Haley & Steele Gallery, 91 Newbury St., 617-536-6339 and www.haleysteele.com.