Map enthusiast Dennis Gurtz of Gaithersburg estimates he has a thousand maps in his collection. Between 200 and 300 of those depict the District of Columbia or adjacent areas, he says. Here, a look at two of his maps. — Kris Coronado
Often called the Arnold Map, this 33-by-30-inch topographical map of the District and the region was designed by civil engineer E.G. Arnold and published in 1862. Benjamin C. Tankersley/FOR THE WASHINGTON POST