This is an article I took from Wiki travel, and below are my comments and advice for all of you. Have a good trip to Hanoi.
Ho Chi Minh Mausoleum (Open mornings only, 8-11AM; closed on afternoons, Mondays, and Fridays. Apparently closed October-December for maintenance of the body. Admission free.)
Oh, what I can say. I went to HCM mausoleum like 5 times when I was a kid. It's kinda boring waiting so long on the line and then having only about 1 minutes to see Ho uncle. However, I love Ba Dinh square and also the bamboos near the mausoleum. Otherwise, nothing here is really interesting!
Ho Chi Minh Museum (19 Ngoc Ha St., Ba Dinh, Hanoi; tel. +84-4 846-3572, fax +84-4 843-9837; Open 8-11:30AM, 2-4PM, closed Monday and Friday afternoons. Admission 10,000 dong.) firstname.lastname@example.org.
Near HCM mausoleum, a lot of stuffs about HCM, only for one who's really interested in history and HCM's life
Ho Chi Minh's Vestige In The Presidential Palace Area (No.1 Bach Thao, Ba Dinh, Hanoi; tel. +84 08044529, fax +84 08043064. Open 7:30-11AM, 2-4PM in the summer, and 8-11AM, 1:30-4PM in the winter. Closed Monday and Friday afternoons. Admission 15,000 dong).
One-Pillar Pagoda&MDASH; Tucked away between the Ho Chi Minh Mausoleum and Museum. Travelers find the One-Pillar Pagoda either charming and lovely or utterly pointless, depending on how many tour groups are crammed into the small grounds at the time of their visit. Either way, it's free.
Yeah, it's small. It is said that an old emperor of vietnam dreamt about a lotus growing in the middle of the lake, so he built that pagoda. That's all
Fine Arts Museum (Bảo Tàng Mỹ Thuật), 66 Nguyen Thai Hoc Street. Only party-approved art is shown here and there is no information in English and only little in Vietnamese. But it is an interesting museum at any rate, with pieces such as the wonderful pictures of soldiers on boats depicted on prehistoric bronze drums, Buddhist art, and revolutionary art of the 20th century wars. Also some interesting silk paintings. Entry is 20,000 dong (in 2009).
Temple of Literature (Văn Miếu) (On Quoc Tu Giam St., south of the Mausoleum. Admission 10,000 dong). The Temple of Literature was founded in 1070 and established as the country's first university six years later. The courtyard features numerous stone tablets, each mounted on the back of a tortoise, with the names of graduates.
You may be confused a little bit about temple and university, but don't worry, that's kind of vietnam. You may, or may not, with a little chance, meet students coming to this temple to make wishes for their studying, or even passing the university examination. And don't forget to "XIN CHU", which is the way that you ask an old man writing for you a word on a red paper (it's not free actually, and not all the time you can buy that, but they said it brings lucky)
Army Museum (Bảo Tàng Quân Đội), Dien Bien Phu Street (Admission 20,000 dong and 5,000 dong to take pictures).
Air Force Museum (Bảo Tàng Không Quân), Truong Chinh Street (southwest of the city center).
National Museum of Vietnamese History (Bảo tàng Lịch sử Việt Nam), No. 1, Trang Tien Street (Admission 15,000 dong/Students 8,000 and under 15 just 2,000. 15,000 dong for a camera/30,000 dong for a video). Hours: 8AM-11:30AM and from 1:30PM-4:30PM.
good for learning more about vietnam
Museum of the Vietnamese Revolution (Bảo tàng Cách mạng Việt Nam), 25 Tong Dan Street (and 216 Tran Quang Khai Street) Open every day except Monday, from 8AM to 11:45AM and from 1:30PM to 4:15PM Admission 10,000 dong. This museum gives a very informed and detailed account of the Vietnamese struggle against first the French (starting in 1858 -- on the first floor), then against the Americians (on the ground floor - ending on 30 April 1975).
Museum of Ethnology, (Bao Tang Dan Toc Hoc Viet Nam) Nguyen Van Huyen St, Cau Giay district. Open every day except Monday, 8:30AM-5:30PM. Admission 25,000 dong for foreigners.
I love this museum, this is really a good museum and you should visit it first before going anywhere else in vietnam, especially SAPA. Besides, this museum attracts the most number of foreigners visiting. And the most important thing, I live near this museum!
Hoan Kiem Lake is a pleasant park in the center of town, within easy walking distance from anywhere in the Old Quarter.
A beautiful lake, hope you can see the giant turtle living in this lake, but it rarely happens. Generally, walking around Hoan Kiem lake is really interesting, and then you can walk to the OLD quarter which is really near this Lake.
Oh i'm tired, I will give you more advice about where else to go in Hanoi, and Vietnam too: SAPA, HCM city, Hue, Hoi An, Da Nang, Halong, Cat Ba Island...