Come to those places, coffee-lovers can experience Hanoi in old time and nowadays with the warm taste of cafe.
Café Giảng 
Café Giảng is humbly hidden on a small lane on Nguyen Huu Huan Street in the city’s old quarter. It may be difficult to find for visitors, but it is well worth the effort.

It continues to be hugely popular among Hanoi’s coffee addicts with its special ca phe trung, or egg coffee. Giang Café was founded by Mr. Nguyễn Giảng in 1946, when he was working as a bartender for the famous five-star Sofitel Legend Metropole Hanoi hotel. Although the café has been relocated twice, its egg coffee recipe is almost the same as in its early days, with its chief ingredients being chicken egg yolk, Vietnamese coffee powder, sweetened condensed milk, butter and cheese.
Café Lâm
One of Hanoi's oldest cafés, this slightly musty one-room establishment is practically a historical monument. Its proprietor, Nguyễn Lâm, provided coffee and often loans to the city's impoverished artist community during the war, and rumor has it that he is sitting on an art collection now worth a fortune. He serves Vietnamese-style hot and iced coffee (with thick, sweet condensed milk) to a crowd of faithful regulars.

It was by accident that Nguyễn Văn Lâm became an art collector. Books were his hobby. And when he wasn't looking for rare books, he was busy starting a cafe in the heart of Hanoi's old quarter. But some of his patrons couldn't pay, and gave him paintings in lieu of cash for long hours spent drinking coffee and talking.The cafe became a gathering place for students and artists in the '50s, a turbulent time as French colonial rule was coming to an end and Vietnam was taking control of its own destiny. Many of the great names in Vietnamese painting passed through here: Nguyen Sang, Nguyen Tu Nghiem, Van Cao and Bui Xuan Phai, renowned for his scenes of Hanoi past.
Café Nhĩ
Among the “the big four” cafes of Hanoi “Nhan-Nhi-Di-Giang”, Nhĩ cafe lies quietly in Hang Ca Street, at the crossroad Hang Luoc – Hang Ca – Ngo Gach.

Without advertising board and having limited area, the coffee shop used to be King café of Hanoi. Coffee are put in porcelain tea pot. The bartender add sugar or milk into coffee and stir until the bubble come before ice being added.
 
Café Năng
Standing in Hanoi for nearly half of century, Café Năng is one of the oldest cafe in town and is busy for most of the opening time. The owner is an old lady with a very sweet smile who wakes up everyday at about 3am to prepare the coffee before walking around Hoan Kiem lake for exercise before heading up to her favorite Pho shop for breakfast. She gets back to her shop (the house is upstairs)and returns to sleep until 12 or 1 pm. Then she goes down to help her daughter to run the cafe. She makes the best coffee, even better than her daughter. The cafe also serves seasonal juices as well, passion fruit juice being my favorite and the staff know that I like to drink it with the seeds while other customers don't.

The cafe's staff changes sometimes but they do remember the customers' choices very well and for me, it's white coffee with lots of condensed milk. Customers sit on low wooden chairs at low wooden tables and in the peak times, people have to sit on the other side of the road but nobody seems to worry about that. They come to Cafe Năng to enjoy the coffee and the great atmosphere. observing the tourists walking by. It's probably the best place for people watching in Hanoi.
Đinh Café
This is a familiar address of the people who love coffee in Hanoi, the shop is listed in the list as the oldest cafe in Hanoi, and with egg coffee is the most prominent dish. Đinh Café is located on the second floor with no signs or signboards.

To reach the coffee shop, you have to go through a tiny alley with narrow wooden stairs and a bit dark. Small space, on the wall hung the black and white photos and a few paintings sketch, when suddenly stepped in, will give the feeling old and nostalgic.