Achasan Mountain

Achasan is only 287 metres and the climb takes about forty minutes on a well-made path, which is why it is the sunrise hill of eastern Seoul - people walk up in the dark on New Year's morning in numbers, and on ordinary days there is a steady traffic of older hikers before six. The ridge looks west over the Han River and the city, so the sun comes up behind you and lights the whole bend of the river and the towers of Jamsil. Along the top are the earth and stone remains of small fortresses built in the Three Kingdoms period, when this ridge was a frontier between Goguryeo and Baekje - several ramparts have been excavated and marked, and the Goguryeo pavilion at the summit explains them. The path continues north to Yongmasan, which has an old quarry face and a paragliding launch, making a longer ridge walk.

What's there

• The sunrise - the Han and the city lit from behind the ridge.
• The fortress remains - Three Kingdoms ramparts along the top.
• The Goguryeo pavilion - the interpretation point at the summit.
• The Yongmasan link - the ridge walk north to the quarry face.

When to go

Year-round; at sunrise for the view the hill is known for. 1 January is extremely crowded. Spring and autumn are pleasantest for the walk itself.

Practical notes

It is a short, easy hill rather than a hike - do not expect wilderness. Paths are busy from before dawn. The fortress remains are low earthworks with signage, not standing walls.

Nearby

The Han River parks at Gwangnaru are below; Ttukseom and Seoul Forest are downstream.