Actually, Captain America can totally run to The Smithsonian
"Either one of you know where The Smithsonian is? I'm here to pick up a fossil."
Obviously everyone was joking around in this early scene from "Captain America: The Winter Soldier." But just for fun, let's say they weren't. That would mean Natasha Romanoff is a pretty bad spy, and Steve Rogers' quip that you can't run everywhere is ridiculous. Why?
The Smithsonian is three blocks away.
In the scene, Romanoff pulls up in a fittingly red-and-black car to pick up Rogers after his morning runs around the National Mall. Judging from my memories of the movie and online images, I would estimate that they are on 3rd Street, near the Capitol Reflecting Pool. That places them 0.7 miles from The Smithsonian, as shown in the map above, traveling on foot.
As stated in the scene, Rogers runs 13 miles in 30 minutes, which translates to 2,288 feet per minute. So Captain America can run to the front door in about 97 seconds.
Then again, given the choice of running even more after completing 13 miles and taking a quick ride in a slick Chevrolet Corvette Stingray, what would you choose?