Useful Information

Climate Korea has four seasons, with a wet monsoon/summer season in July and August and a cold winter from November to March..The ideal time to visit Korea is during the autumn months (September-November). During this time, the country exhibits warm, sunny weather, skies that are cobalt blue and spectacular foliage that is perhaps the biggest draw card.
Currency & Currency Exchange
The unit of Korean currency is Won. Korean monetary units are KRW10, KRW50, KRW 100, and KRW 500 coins, and KRW 1,000, KRW 5,000, KRW 10,000 and KRW 50,000 notes..Major currencies and traveler’s checks can be exchanged into Korean won at the airport, hotels, and at all Korean banks. Credit cards, e.g. VISA, Master Card, American Express, and Diners Club, are all widely accepted.
Time Difference
Standard Time in Korea is 9 hours ahead of Greenwich Mean Time (GMT +9)..

Business Hours .
Government offices : 9:00 a.m. ~ 6:00 p.m. (Monday through Friday)
Bank : 9:00 a.m. ~ 4:00 p.m. on weekdays
The standard voltage in Korea is 220 volts AC at 60Hz. The outlet has two round holes and is the same type used in France, Germany, Austria, Greece, Turkey, and many other countries.
Tipping is not a traditional Korean custom. Service charges are added to the bill but tipping is not expected. It is also not necessary to tip a taxi driver unless extra services are provided.
All foreign visitors entering the Republic of Korea must possess a valid passport. Delegates, except those from countries who have visa exemption agreements with Korea, should apply to a Korean diplomatic mission in their countries for visas prior to departure. 

Korea Immigration Service
Travel Guide to Korea

Travel Guide to Seoul
Incheon International Airport