The district which contains the administration office of the province is the Amphoe Mueang (lit. town district). The district should not to be confused with the capital town itself, which is a different administrative entity usually much smaller than the district. Until the 1930s most of the capital districts had names just like other districts, whereas districts dating back to old provinces had the word Mueang in their name. In 1938 all the capital districts were renamed to Amphoe Mueang, whereas in all non-capital districts the Mueang was removed from the name. The notable exception to this rule is Ayutthaya, where the capital district is named Amphoe Phra Nakhon Si Ayutthaya (instead of Amphoe Mueang Ayutthaya) – the same as the province, which is fully named Phra Nakhon Si Ayutthaya. Also the capital districts of Thonburi and Phra Nakhon provinces had the same name as the province, which they kept when the two provinces were merged to form Bangkok metropolis.
In most cases the capital district is also the most populous district of the province, as the provincial administration is usually located at the largest town of the province. Songkhla Province is the most striking exception, as the town (and thus also the district) Hat Yai grew much faster than the capital Mueang Songkhla due to its better transport connection.
There are four districts in Thailand (Chan, Pan, Suang, Yang) which contain the term Mueang in their name as well, even though they are not capital districts. All of these were created relatively recently between 1973 and 1995.
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