There is a hall in Chedi Luang Temple in Chiang Mai, Thailand where women are not allowed to enter. Why?

There is a hall in Chedi Luang Temple in Chiang Mai, Thailand that women are not allowed to enter. The reason why women are not allowed to enter is because the Inthakin City Pillar, the "city pillar" of Chiang Mai, is enshrined there. Below the city pillar is a multi-layered base, and above is a standing Buddha statue.

In the folklore of Chiang Mai, the Phra In city pillar was built by the god Phra In for the stability of Chiang Mai, and used the city pillar to warn the people of Chiang Mai to abide by The five precepts of Buddhism. The people of Chiang Mai believe that the city pillars represent the prosperity of Chiang Mai and the happiness and well-being of life. In the minds of Chiang Mai people, the tower seal pillars are sacred and cannot be desecrated. Until now, people still abide by ancient precepts and do not allow women to come into close contact with city pillars because they think women, especially women during their menstrual period, are unclean.