I loved every day of this trip, but highlights included:
Hanoi - the remains of Hoa Lo Prison (dubbed the "Hanoi Hilton") and getting lost wandering the streets of the Old Quarter taking in the sights and sounds of everyday street life
Halong Bay - sailing among the picturesque limestone peaks and the fantastic seafood on board
Reunification Express - no trip would have been complete without riding on this train which unites North and South
Hue - dragon boat ride along the pefume river stopping to see the stunning mausoleum of Tu Duc, and to see the impressive Thien Mu Pagoda. The Imperial Citadel tour was also a highlight. An optional King and Queen night allowed you to dress up and dine with traditional music played whilst eating - completely tourist-driven, but memorable nonetheless
Hai Van Pass - stunning views to the ocean
Danang - walking on China Beach and dipping a toe in the sea, and walking up the steps to Marble Mountain to see the impressive caves used as a hospital by the Viet Cong during the war
Hoi An - beautiful small town with historic buildings and oodles of charm. Apparently nicknamed the culinary capital with a buzzing riverside market. Each shop-front is also obliged to have lanterns hanging, which look beautiful come evenings.
Ho Chi Minh City - vibrant metropolis with lots to see and do. I enjoyed sitting in the cafes watching the world go by, the crowds at the Ben Than Market, and Saigon Skydeck (Bitexco Tower) watching the city from the 49th floor. I particularly enjoyed the Reunification Palace whose architecture and interiors were pure 1970s kitsch, along with the basement's military command centre, still equipped with old rotary-dial phones and radio equipment. The War Remnants Museum had some haunting photographs. I would strongly advise taking a walk to the Old Post Office (designed by Monsieur Eiffel), Notre Dame Cathedral, and if you get chance wander to the Ho Chi Minh City Museum and Fine Art Museums which are housed in grand old colonial buildings. Although you can't enter the Hotel De Ville, it is certainly worth viewing from the exterior. The Municipality Building (Opera House) although only open for twice-monthly performances is also worth viewing from the outside. The Sri Thendayyutthapani Temple is also well-worth visiting with a very interesting rooftop tower.
Try to make time to enjoy the rooftop garden at The Rex Hotel, The Saigon-Saigon Rooftop Bar at The Caravelle Hotel, and Level 23 at The Sheraton Hotel, which all have great views.
Cu Chi - tunnels are a must-see with interesting demonstrations of the traps the Viet Cong used to set, a shooting range and, although widened for Westerners, a very claustrophobic and humid short-section of tunnel to crawl through
Mekong Delta - riding in a traditional wooden sampan and an enjoyable homestay
Although this trip is marked as Moderate, I have been on Exodus trips labelled as Leisurely which have been more exertional, so fear not.
There is a great balance of sight-seeing and free-time. I booked this trip for January as although I knew the weather may not be perfect in the North - Hanoi and Halong Bay - (10-15 degrees C with some drizzle and clouds), I was aware that in the South it would be warm (30 degrees plus). Rainy season in the South is from April, although I hear it only rains for short bursts each day, but is incredibly humid.
Internet availability was excellent throughout Vietnam and wifi is freely available in all the hotels.
Take a bunch of $1 bills for buying mementos, and try and get smaller notes of Dong prior to going to Vietnam - 50,000, 100,000 and 200,000 should be fine. The ATM will only let you withdraw £60 at a time, although this does equate to 2,000,000 Dong. Aside from Ho Chi Minh City - you can eat and drink well for very little.
You don't need walking boots for Marble Mountain