The National Mall is a US National Park located in downtown Washington DC, just east of the Potomac, across the river from Arlington, Virginia. The area commonly considered the National Mall, from the Lincoln Memorial to the US Capitol Building, measures almost two miles, with many monuments, memorials, and museums along the way. The Smithsonian Institution sees over many popular museums located on and around the National Mall.
Once you're at the Mall, walking is most common way to get around and see the attractions, but with monuments far apart, it is best to split the trip into bite sized pieces. Visitors can also find companies which will rent bicycles (or can use DC's bike sharing program, Capital Bikeshare). Guided Segway tours are also available from some companies. Both alternatives to walking will give tourists who are short on time a way to see more and save some energy.