Flower Market
The flower market was right next to our hotel and is open 24hours a day. We visited about 9PM on a sunday night and there was still all sorts of life and activity for the artisans making flower arrangements and selling bulk flowers. It's really cool seeing a sprawling complex dedicated exclusviely to selling flowers and flower art at all hours of the day.
Food
Our food experience in thailand was different from the food experience we were expecting. We spent a lot of our time searching out street food only to discover that most of the best thai food came from nicer establishments instead of off the street. The spices and flowers in the markets were beautiful and everything about the food culture in Bangkok was phenomenal.