Free museums on the National Mall
The question behind this one is usually “which museum is the one to see”, and I am not going to hand you a most-visited ranking I have not verified. What I will say from nine summers of pointing people at buildings: Air and Space and Natural History are the two that consistently draw the biggest crowds, and Air and Space is the one that needs a pass. Sort the pass out before you leave your hotel, from si.edu, and let the rest of the day move around it.
The practical value of free entry is that a museum is not a commitment. Walk in, give it 40 minutes, walk out when the children have had enough, and you have lost nothing. That also makes the museum row the cheapest weather plan in the city, which matters when the rest of the Mall has very little shade and no roof.
Museum hours are the only clock on the Mall. The buildings shut in the late afternoon while the memorials stay open and lit all night, so put the museums in the middle of your day and the memorials at either end.
If you want to string them together with the memorials, the hour-by-hour version is on one day on the National Mall. If your legs are the limit, the $45 hop-on hop-off ticket is valid 24, 48 or 72 hours across 18 stops and boards opposite the International Spy Museum, though buses come every 30 to 45 minutes and the audio can drift out of sync with the bus.
Frequently asked questions
How many free museums are on the National Mall?
Eleven Smithsonian museums sit along the National Mall itself, and six more plus the National Zoo are nearby, making 17 free museums in the DC area. Every Smithsonian DC location is free, with no admission charge at any of them.
Do you need tickets for the Smithsonian museums?
Not for most of them, but the National Air and Space Museum in DC requires a free timed-entry pass and opens 10:00 a.m. to 5:30 p.m. Get the pass from si.edu before you arrive. Nothing about it costs money — see is the National Mall free.
Which Smithsonian museum should I visit?
Air and Space and Natural History are the two that consistently draw the biggest crowds, and Air and Space is the one that needs a timed pass. I would not rank them beyond that. Because entry is free you can try two in an afternoon — the running order is in the one-day plan.