Why is Washington D C a special city?

Answer 1

It could be because:

# of it not being a part of any U.S. state, only city in the US like this. # of it being the heart of U.S. Federal Government # of it holding many memorials to heros and soliders # of it's location between Maryland and Virginia on the Potomac River

# of it's history.

Answer 2

Cherry blossom festival, warm weather, tourism...