I went to Vietnam as part of my one-month-trip after my bachelor's. Together with a friend from university I travelled from Singapore, to Cambodia, to Vietnam, then back to Singapore and on our way back to Germany we made a 10d-stop in Sri Lanka.
The general plan in Vietnam was to go from north to south per train and visit cities along the track. We landed in Hanoi and had a flight back to Singapore from Ho Chi Minh City.
From Hanoi we started two trips. One to Hạ Long Bay and one to Sa Pa in the north, close to the chinese border. Hạ Long Bay is a UNESCO World Heritage Site and features thousands of limestone karsts and isles in various shapes and sizes. After these two trips we took a train to Hội An which is almost in the middle of Vietnam. Hội An is also a UNESCO World Heritage Site due to its preserved history as a trading port.