Eungbongsan

Seoul Forest

The park is open 24 hours and never closes, but almost everything worth timing inside it does — the ecological forest, both conservatories and the floor fountain all keep separate hours, and the two indoor ones shut on Mondays. Tents, sun shelters and awnings are banned outright, which is the rule most picnic plans get wrong.

Dongdaemun Design Plaza

It closes three days a year and otherwise runs 10:00 to 20:00, but that figure covers the site, not what is inside it — each hall keeps its own hours according to whatever exhibition is running. Check the programme, not the building.

Leeum Museum of Art

An art museum run by the Samsung Foundation of Culture. The standing exhibition of historic Korean art is free and the special exhibitions are ticketed, priced per show rather than at a standing rate. From exit 1 of Hangangjin Station, the route runs 100 metres towards Itaewon, then turns right into the first alley for an uphill walk of about five minutes.

Heunginjimun Gate

The eastern gate of the walled city, designated a Treasure in 1963. A crescent-shaped barbican wraps its outer face — the only one of the four main gates built with one.