Security is so tight around the Blue House (so called because of its blue tiled roof) at the base of Bukaksan that even innocently walking past the presidential residence is likely to get you stopped and questioned by mirror-glassed special agents. However, it is possible to see inside if you join a free 40-minute tour, which must be pre-booked online at least 20 days prior, but is not really worth the hassle involved.
Bring your passport and join the tour at the ticket booth in Gyeongbokgung’s car park. A tour bus then takes you the short distance from the car park to Cheongwadae’s public entrance. On arrival you'll be shown a five-minute film then whisked around the palatial grounds, which are nice enough.