I am writing this because there were only a few itineraries from Singapore so I hope this would help you in your travel planning. I love travelling in Korea! The food was great but there was a lot of hiking and luggage carrying! :)))) Documents to prepare  1. K-ETA ($12.78) (Electronic Travel Authorisation) 2. Q-code (do prepare accommodation address+phone number) 3. 24h pre-departure ART swab 4. On-arrival PCR test ($85.38)   5. Seoul Discover Pass (to buy 2 days before on Klook/1 day before using the app)  6. 4G Sim card 10-day unlimited data (to buy on Klook before arrival, to collect at the airport) 7. Vaccination certificate (Notarise)  8. Korea Air and KTX Busan train tickets  9. Travel insurance ( $35.20 from Grab) Most importantly, print your vaccination certificate and prepare e-copies.  Apps to download:  1. Naver Maps (highly useful and has GPS function)  2. Subway Korea 3. Kakao Taxi  4. Kakao Talk 5. Discover Seoul Pass  6...