Uljin County, North Gyeongsang Province (South Korea)

Here is gif image of flag.
http://www.traveltimes.co.kr/news/articleView.html?idxno=104913
https://www.youtube.com/watch?v=s5WZYsZg3-4
Tomislav Šipek, 12 January 2020

From the Uljin website:

[The flag] represents the sun, mountains, fields and ocean and [symbolises] clean environment and rich tourist resources, especially the 울 shape mean[ing] the development in the miliennium age, showing a dynamic motion. [The red represents] the sun rising over the offshore of Uljin. [The gold represents the] famous spa of Uljin, [The green represents the] clean mountain and field [and the blue represents the] clean ocean. The [symbol] 울, the initial of Uljin's Korean name represents clean and [the] well off environment of Uljin.

researched by Phil Nelson, 19 October 2005

[Ed.: Editorial revisions in brackets]