In the bustling capital city, you need to put the street crossing skills you learned in Saigon to use again as the traffic is constant and hectic.
Hanoi is cool . It has a mix of old French colonial flair as well as distinct Vietnamese culture. Yet, the best thing about Hanoi is that there is a proper backpacker's hostel here run by a couple of Australian guys. The place is awesome and makes meeting people easier and city exploration a little more fun. If you come here, check 'em out. There's lots to do here with museums and tourist attractions but the most interesting for me was what remains of the Hoa Lo Prison. Or as the U.S. pilots called it who were held prisoner here.... The "Hanoi Hilton".  Most of it was torn down to build a shopping plaza (genious!) but some bright soul must have realized you can charge tourist 25 cents to enter what remains and they will pay. It's not bad actually and there are photos of Senator John McCain visiting the prison museum back in 2000. He was shot down over North Vietnam and held as a POW for over 5 years during the war. He spent some of his time here. It must have been hell. Most of the prison, however, is dedicated to all the Vietnamese revolutionaries who were held here by the French before their independence.
So anyway, Hanoi is fun and a great city to walk around and take photos.