Seoul's hotspots have a different flavor in each zone: indie live music in Hongdae, global dining in Itaewon, luxury shopping in Gangnam, and industrial cafes in Seongsu-dong. Here is the vibe, route, subway access, and peak hours for all four zones.

Four zones at a glance
- Hongdae (Line 2 Hongik Univ.): indie music and busking, around 30 live clubs, a Free Market (Sat 13:00-18:00 at Hongdae Playground). Peaks Fri-Sat evenings
- Itaewon (Line 6 Itaewon, Noksapyeong): restaurants from 50+ countries within a 500 m radius, 70%+ English menus, club entry 20,000-40,000 won with a welcome drink
- Gangnam (Line 2 Gangnam, Line 9 Sinnonhyeon): COEX Byeolmadang Library (13 m shelves), Lotte World Tower Seoul Sky (123rd floor, 27,000 won)
- Seongsu-dong (Line 2 Seongsu): 200+ industrial cafes and pop-ups in converted factories, Seoul Forest a 15-minute walk away

Subway routing
All four zones link with two or three transfers. Hongik Univ. to Itaewon is Line 2 to Line 6 (transfer at Hapjeong, about 30 min), and Gangnam to Seongsu-dong is a direct Line 2 ride (about 20 min). To hit all four in a day, start in Seongsu in the morning and end in Itaewon at night.
In short: Hongdae for music, Itaewon for global dining, Gangnam for luxury and views, Seongsu-dong for design cafes. You can tie them together in a day with two or three transfers, and a morning-Seongsu to night-Itaewon flow is the most efficient.