Da Lat has an airport. I have flown there from Ho Chi Minh, as recently as March. There's a lot of intriguing things to do and see there. There's an old post from jiejie in this forum where she laid them out. One high point was the Gaudi-esque compound built by the "crazy woman". The summer palace of the last king of Vietnam is well worth touring.

We went by car down the hill from Da Lat to Nha Trang and ate at a quaint restaurant near Nha Trang surrounded by lily ponds. Yes, there are a lot of tourists in Nha Trang, but there is also a beautiful beach. And depending on the hotel one chooses, you can isolate yourself from the touristic area of town.