February 3, 2016 on Fodors.com || Washington D.C. is one of the country’s most visitor-friendly cities. It’s easy to get around, the major sights are concentrated in a wonderfully walkable area, and the city has an enviable mix of history and new offerings. But to do the nation’s capital properly, there are a few no-nos that you should avoid. For example, don’t buy one of those 3-for-$10 FBI T-shirts. And don’t try to pick the cherry blossoms. Most important of all, don’t do any of these 10 things. See full slideshow>>