American History Museum
Natural History Museum
Vietnam Memorial
Korean War Memorial
Lincoln Monument
Zoo
3D IMAX show at Air & Space Museum
Lunch at Chinatown Express in Chinatown
Holocaust Museum (If no young children)
The Mall for a nice walk

In no particular order! Enjoy your trip

FDR Memorial
National Cathedral

Natural History Museum
new National Museum of the American Indian
Walk on the Mall from Capital to Lincoln Memorial
FDR Memorial
Dupont/Adams Morgan
Holocaust Museum
Georgetown waterfront
Drive/walk along Embassy Row
walk around tidal basin/Jefferson Memorial

The weather is going to be great here, enjoy your visit!

FDR memorial
Arlington cemetary
Jefferson memorial
Walk around the tidal basin
American history museum
All the war memorials near Lincoln memorial
US capitol
Georgetown waterfront/ C&O towpath

Take good walking shoes, DJ!

Visiting the Mall took two days for us. Distances are deceptive.

Try to fit in the Botanical Gardens at the top of the Mall, near the Capitol, and the National Gallery of Art, just about at the center.

Find a way to have dinner at the Brickskeller in Dupont Circle! The foods are pub grub, but they have the largest beer menu in the world, as certified by The Guinness Book Of World Records, and two juke boxes that are legendary. Sheer fun.

I grew up near D.C. and just last year took my first bus tour. It was fun and well-done and you can see much in one day as you can get off at one spot and pick up another for one fee paid at the start. I do suggest it!
The Vietnam Memorial and the WWII Memorial are awesome. Do NOT miss the Lincoln Memorial - & Arlington to see JFK's gravesite...pretty inspirational.
A Happy Hour suggestion - the Sky Terrace atop the Hotel Washington. GREAT VIEW!!!

The Air and Space Museum
The Washington Monument
The Vietnam Memorial
The Korean War Memorial
The World War Two Memorial
The American History Museum
The Natural History Museum
The National Zoo
Mount Vernon
Lauriol Plaza off Dupont Circle to eat

Noone has mentioned the LOC yet - the Library of Congress. I went twice in two days during my trip to DC last summer.

Wonderful history, architecture, interesting exhibits, etc. Easily combined with the Capitol tour and Botanical gardens.

Arlington Cemetery tourmobile also enjoyable, but crowded.

I posted a trip report in October, it reads a bit 'valley girl', but has the sights I found worthwhile. (not sure what I was thinking when I wrote it!)

Don't miss the Spy Museum!

And never, never visit DC without seeing the changing of the guard at the Tomb of the Unknowns.

If you need a break from the big sights, and enjoy historic homes/architecture, I'd recommend Woodrow Wilson's house. It's near DuPont Circle, which would be a great place for shopping and eating (or more walking around looking at beautiful architecture).

Postal Museum
National Building Museum
Folger Shakespeare Library
Dumbarton Oaks
Tudor Place

Look into the nighttime 2 hr. bus tours of DC - save your feet & enjoy the monuments at night. Particularly good if you get in the late afternoon - or you CAN drive around the mall at night - the ONLY time I would recommend a tourist drive in DC, M-F. Enjoy the peak of the cherry blossoms - go EARLY before the mobs.

ttt for recent post asking for DC info

1. Lincoln Memorial, day or night.
2. Jefferson Memorial, night
3. Vietnam Wall
4. Spy Museum
5. National History Museum
6. National Gallery of Art
7. Library of Congress
8. Botanical Garden
9. Declaration of Independence, can't remember where it is, Commerce Bldg?.
10. Mt. Vernon
11. Air & Space/IMAX theatre
12. The Falls in Potamac, can't remember the name.
13. Georgetown!!! and the National Cathedral!!! and the B&O CAnal!!!
14. Baltimore...

I'll second the recommendation to never visit DC without seeing the changing of the guard at the Tomb of the Unknowns in Arlington Cemetery. While you are there, it is also worth seeing JFK and Jackie O's graves. The eternal flame that burns there can be seen from all over the city at night.

Smithsonians:
Air & Space
American History

Do a tour of the monuments at night.

In addition to all those wonderful suggestions, I'd add the National Portrait Gallery.

The view from the top of the old post office tower is great, and a cool place to be on a hot day.

Don't miss the Lincoln Memorial. Take your time.

I'm not listing 10 but the number 1 site is:

Mount Vernon, George Washington's home

This place is extremely enjoyable to walk around and it is a gorgeous place on the banks of the Potomac only about 10 miles south of D.C.

1. Lincoln Memorial (at night)
2. Vietnam Memorial (at night)
3. Einstein statue
4. "Awakening" sculpture at Haines Point (definitely during the day)
5. Old Town Alexandria
6. Drinks on the roof of the Hotel Washington
7. Dumbarton Oaks
8. National Building Museum
9. American History Museum
10. Breakfast at Eastern Market

ttt

Ttt, still relevant!

you're very correct, travelphile! I'm not sure if the Udvar Hazy Air and Space Museum (near Dulles airport) was built when this thread was started, but at the recommendation of a fellow Fodorite, my family and I went and loved it! It's much less crowded than the Air and Space Museum on the Mall, and my nephew was in heaven walking around the SR-71.

My top 10
1. Udvar Hazy A&S (could have made this all 10 choices)
2.Portrait Gallery
3. All the Monuments
4. Arlington Cemetery
5. A&S Museum
6. Newseum
7. Capitol Tour
8. Outside of White House (havent done tour)
9. American History Museum
10. Old Post Office Tour

Too hard to choose and opinionated... Still very relevant and a worthwhile thread.