Achasan (아차산, 峨嵯山) is part of a ridge forming the eastern boundary of Seoul (separating it from the neighbouring city of Guri in Gyeonggi-do province), the highest point of which is Yongmasan (용마산, 龍馬山, Dragon Horse Mountain) at 348m (Achasan’s a subsidiary peak at 287m, though the entire ridge is colloquially referred to as Achasan); although not the highest mountain in Seoul it has awesome views, so it’s easy to reap good reward for fairly little effort with a quick 45-minute hike from Achasan Station (Line 5) to the best viewpoint.
The ridge has a network of hiking trails with one main trail running the length of the north-south ridgeline; this is actually part of the Seoul Trail (a 157km trail around the city’s periphery), forming the section from Yangwon Station (Gyeongui-Jungang Line) to Gwangnaru Station (Line 5). If you do want to exert yourself a little more than a quick up & down from Achasan Station, you can follow the Seoul Trail from Yangwon to Gwangnaru for a hike of around 8km (see bottom of page for pics)
The first route described here starts from Achasan Station, goes about halfway to Yangwon, then detours up to the top of Yongmasan (which isn’t actually part of the main trail) before finally descending steeply to finish at Yongmasan Station (Line 7).
From Achasan station take exit 2, then immediately turn left onto this street:
At the end, turn right (there’s a kendo dojo there which may or may not have this inflatable kendoka out front):
Follow the road as it bends round to the left, then turn left on Jayang-ro and you’ll see the mountain up ahead:
Walk towards it and then fork right on Jayang-ro 50-gil and head up past the restaurants, cafes, and hiking gear shops:
Keep going straight at the top until the road turns left in front of this temple:
…follow the road round to the left:
…and these steps on the right are the start of the hiking trail:
It’s about a 15-minute walk from the station up to the trail.
Once you’re on the trail it’s straightforward enough to navigate, just keep walking up and go straight ahead at the various intersections with other trails, and after about 15 to 20 minutes you’ll arrive at the Goguryeojeong pavilion:
The pavilion has some nice views:
…but push on another 5 minutes above the pavilion and you come to a viewpoint with wooden decks, binoculars, and awesome views of southeast Seoul (see picture at the top of this page; Lotte World Tower is prominent, and you can clearly make out Gwanaksan (middle) and Namsan (right) on clear days)
You can also look down the other side of the ridge to Guri:
If you’re only looking for a quick tramp with smashing views, just walking up to this viewpoint and then descending the same way to the station makes for a satisfying little hike.
Otherwise, once you’re done taking photos keep heading north; the trail now takes you past a series of archeological sites, ancient forts that were built along the ridge during the Goguryeo period. Most of them are quite modest, like Achasan Fort 1:
There are plenty more nice views as you hike along the ridge (though none quite as good as the main viewpoint you already passed):
About half an hour on from the pavilion & viewpoint you reach Achasan Fort 4, which is rather more impressive than the others you pass:
Just after Fort 4 there’s a fork in the path; take the wooden steps going down to the left to follow the main trail, not the dirt trails to the right. These steps take you slightly downhill and then up again to a wide open clearing with a helipad marked by a big stone H. From here the main trail to Yangwon Station keeps going straight north (i.e. the reverse of the route at bottom of page), but to reach the highest point on the ridge at Yongmasan you should take the left turning from the clearing. A short distance later you pass through another clearing with a helipad, then a little open-air gym (a fairly common sight on Seoul’s mountains), and then finally the trail climbs up to the summit of Yongmasan:
I just love the fact they have a selfie stand up there!
It takes about 30 minutes from Achasan Fort 4 to the top of Yongmasan, from where it’s a short, steep descent back to suburbia. To get down to Yongmasan Station, find the trail on the other side of the summit marker. This trail down takes about 40 minutes, is fairly rough, and gets pretty steep in places; you don’t really want to get caught on there in the dark or in bad weather (and may want to avoid it in winter). The steeper sections have fixed ropes:
There are more great views as you descend, now of northeast Seoul (Namsan visible to the left, Bukhansan & Dobongsan to the right):
And you pass by another little fort (more like a pile of loose rocks), Yongmasan Fort 7:
At the bottom of the trail you walk past the apartment buildings of a residential area and finally emerge on a main road (Yongmasan-ro); turn left and walk for 10 minutes or so to reach Yongmasan Station.
(There’s also a waterfall in the vicinity of the station; look for signs or check Google Maps for Yongma Waterfall Park, 용마폭포공원, Yongma Pogpo Gongwon. Apparently it’s the tallest artificial waterfall in Asia)
Following this route from Achasan Station to Yongmasan Station takes about two and a half hours at a decent pace with some time for photography stops, though of course you could take much longer over it.
Yangwon to Gwangnaru via Seoul Trail
To walk the whole Achasan ridge from north to south, make your way to Yangwon Station on the Gyeongui-Jungang Line. Leave the station by exit 2 and start along this road:
Almost immediately on the left is a park entrance and this map:
Head through the park, following the Seoul Trail signs for Mangu Cemetery:
At this point cross the bridge and head up the road to Mangu Cemetery:
Mangu Cemetery’s the final resting place for many famous Koreans, including independence activists, writers & poets, and scientists. It also has great views across northeast Seoul towards Bukhansan and Dobongsan:
Once you reach the cemetery, continue by following the signs towards Jungang Observation Point (from where the above pic was taken), then Yongmabong (용마봉, which means Yongma Peak i.e. the summit of Yongmasan). On the way you pass this rest stop with a little help yourself library:
You’re still walking along the same vehicle road (with next to no vehicles on it) after you leave the cemetery, then continue straight on past the library (don’t follow the road up to the left at that point), and eventually the paved surface ends and you’re finally on a proper hiking trail. The steep sections have wooden flights of steps (there’s a particularly long & steep one!), and then you’re up at a good height with views down over Guri to your left:
A short distance further you reach the helipad which is the turning point for Yongmasan:
At this point you can turn right for Yongmasan (and finish at Yongmasan Station), or keep going south along the trail to finish at Gwangnaru Station (by following the signs) or Achasan Station (by turning down at Goguryeojeong pavilion i.e. reverse of the route described at the top of the page).
Starting from Gwangnaru
If you want to start from Gwangnaru Station, come out of exit 1 and just up the road is this tall Seoul Trail sign pointing the way to the right:
You then have to find your way through a residential district. Keep your eyes peeled for the arrows and signs:
The roads give way to some colourful alleyways:
Which bring you to this path up to Achasan Eco Park:
The parks’s full of mythological statues, including this mermaid at the bottom of the park:
The trailhead’s at the top of the park, here:
Turn right and you’re on your way!
Click here for more hiking in Seoul
Achasan’s a great little hike, and it has the best views of Seoul you can get without going all the way up Dobongsan, Suraksan, Gwanaksan or Bukhansan. Have you done it? How was it? Any questions? Leave me a comment below!
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Thank you for posting this! I am planning on doing this hike in April this year. Are there any animals or terrain, like rock scramble, that I should be cautious of?
You don’t see any large wild animals in Korea, and while there are some venomous snakes you’re unlikely to encounter them (I’ve never seen one there). The terrain on the main Achasan trail is pretty gentle, but it is very steep if you do the descent via Yongmasan.
Should be a lovely hike in April, enjoy!