Washington Better

What is a better vacation- San Francisco or Washington DC?
I am wanting to plan a trip and was wondering if San Francisco or Washington DC is better. Which is cheaper? Has more to do? I was thinking of spending about 5-7 days there. Any suggestions?
It really depends on what you want to see/do.Both are comparable in costs but both offer much different things to see/explore. All Smithsonian museums in DC are free, as well as most monuments and other tourist attractions (zoo, national parks, etc) making it a good trip. What will be your travel cost? You may wnat to consider the money you will spend/save by traveling (air, car, train, etc) to each place from where you live that may be a big factor. Both have hotels that you can find good deals at I’m sure…You really need to look at all the costs and think about what you actually would like to see more from each place.
this bitter earth – shutter island