RAINBOW99 and 윤재호 (Yoon Jaeho) share equal billing on 관악산, put out through POCLANOS in September 2025. The title is a place — a mountain on the southern edge of Seoul — and the English gloss in the title exists because that is not obvious from the romanisation.

The word “mountain” is already inside the title

Korean mountain names end in 산 (san), which means mountain, so 관악산 is Gwanak plus san. Written in the Latin alphabet it becomes one opaque word, Gwanaksan, which is why the artists appended “Mountain of Seoul” for anyone outside Korea. The same habit runs through Korean geography: 강 for river, as in 한강, and 대교 for a major bridge. Gwanaksan is real and unremarkable to locals — it rises on the city’s southern boundary, and the Seoul district beneath it, 관악구, takes its name from the mountain rather than the other way round.

About this release

The music video was published on the POCLANOS channel on 25 September 2025, with POCLANOS on the copyright line. It is credited jointly to two acts rather than to one artist featuring another, and no album or EP title is attached. The official description carries only the title and three hashtags: #Rainbow99, #윤재호, #관악산.

Watching from outside Korea

Expect no subtitles; independent Korean releases rarely carry them. If you go looking for the streaming version or for either artist’s back catalogue, searching the Korean spelling 관악산 returns cleaner results than Gwanaksan, which mostly turns up hiking guides.

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