One of many riverside pavilions along the Mekong in Nong Khai
A considerable amount of the riverside area in central Nong Khai has been developed into a sort of promenade, with nicely paved walkways, numerous open air pavilions to sit in, and a few well maintained docks for river cruises. The developed area runs for around a kilometer.
For most of its length, Tha Sadet Market backs onto the walkway. The market is a general wares shopping area, consisting of several covered streets. While there are a number of souvenir shops, the bulk of the market is everyday things like pots, pans, cheap clothing and other household goods.
There are a number of restaurants along the promenade, some of which back onto the market as well. A few have second floors, which may give you a better view of the river.