With around 2,000 miles of coastline, Vietnam does have a fair number of beaches, although not as many as you might think. The best beaches are in the southern part of the country. There are some nice beaches in the north near Hanoi, but the weather is really only suitable from May to July or August.
The list below is organized north to south, starting with one of Vietnam's most famous beaches, to watchers of American television.
The name "China Beach" is apparently an invention of American television, but this 20 mile stretch of sand near Danang really was used by American soldiers as an "R&R" stop. The weather here is quite cool in the winter, but from April or May until August it can be quite nice. The beach was the site of Vietnam's first international surfing competition in 1992. Conditions for surfing are best from September to December.
The beach is home to one of Vietnam's most luxurious beach hotels, the Furama Resort. Danang, Marble Mountain, My Son and Hoi An can be explored by day-trips from China Beach.
South-Central Vietnam's Nha Trang is the closest thing Vietnam has to an "international" beach resort destination. The waters are still clean and clear, making for good diving conditions. Nha Trang can be reached by air from Saigon, Hanoi and other cities.
The beach at Vung Tau isn't especially great, but its proximity to Ho Chi Minh City insures a steady patronage from locals as well as tourists. Vung Tau is about 80 miles from Ho Chi Minh City and can be reached by hydrofoil from the city.
Phu Quoc Island
According to many, the beaches of Phu Quoc island are the best in Vietnam. The island lies off Kampot in Cambodia and is in fact claimed by Cambodia. The island can be reached by air or by ferry from Rach Gia on the mainland.