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North of the current city center along the banks of the river is the former governor's mansion. It was built around 1912 to 1914 for the first governor appointed from Bangkok. It was a time when there were still tensions with the colonial French across the Mekong, so the house was strongly built to resist attack, and even had a sort of bunker in the basement.
The exterior of the former governor's mansion, now a museum.
In 1955, when the current king of Thailand visited, the current governor had the house renovated for the king's use on his one night in town. However, once the king left it would have been unseemly for the governor to sleep in the same room and so the house was abandoned and unused for more than 50 years.
The bedchamber where the king slept in 1955
Around 2008 it was decided to restore the old mansion, which was now run-down, and open it as a museum. The house has been made to look as it did when the king stayed there, right down to the furnishings of his bedroom. The first floor of the building contains displays about the history of Nakhon Phanom, with an emphasis on the last 100 years or so, while the second floor is devoted almost entirely to his majesty's 1955 visit.
The museum is open Wednesdays to Sundays from 10:00 am to 6:00 pm. It is closed on Mondays and Tuesdays. Admission is free.