via Bangkok Post, 28 October 2018:

Estimated at over 200 years old, this small town is famous for blending the architectural heritage of the Islamic religion with a Sino-Portuguese style, a genre of Southeast Asia architecture.
Muang Songkhla is included among seven cities that the Thai government wishes to propose to Unesco to list as a World Heritage site.
The other six are Muang Chiang Mai, Muang Lampang, Muang Kamphaeng Phet, Muang Lop Buri, Muang Phimai and Muang Nakhon Si Thammarat.
Source: Songkhla town closes in on World Heritage status | Bangkok Post: news