Lak mueang (Thai: หลักเมือง) are city pillars found in most cities of Thailand. Usually housed in a shrine (Thai: ศาลหลักเมือง) which is also believed to house Chao Pho Lak Mueang (เจ้าพ่อหลักเมือง), the city spirit deity. They are held in high esteem by citizens.
It was probably King Rama I who erected the first city pillar on 21 April 1782, when he moved his capital from Thonburi to Bangkok. The shrine was the first building in his new capital, the palace and other buildings being constructed later.
Shortly after the shrine in Bangkok, similar shrines were built in strategic provinces to symbolise central power, such as in Songkhla. More shrines were created during the reign of King Buddha Loetla Nabhalai (Rama II) in Nakhon Khuen Khan and Samut Prakan, and by King Nangklao (Rama III) in Chachoengsao, Chanthaburi, and Phra Tabong Province (now in Cambodia). However, after King Mongkut raised a new pillar in Bangkok, no further shrines in the provinces were built until 1944, when then-Prime Minister of Thailand Phibunsongkhram built a city pillar in Phetchabun, as he intended to move the capital to this town. Though this plan failed to get approval by the parliament, the idea of city pillars caught on, and in the following years several provincial towns built new shrines. In 1992, the Ministry of Interior ordered that every province should have such a shrine. As of 2010, however, a few provinces still have no city pillar shrine. In Chonburi the shrine was scheduled to be finished by the end of 2011.