Fresh off the heels of my last hike...
First, let's just say it's "in Europe" because it's best accessible from Europe...
Second, a huge disclaimer: everything I write here can very soon be outdated. With the construction of international Airport in Nuuk Air Greeland stopped operating flights to Kangerlussuaq. Current flights from Copenhagen are chartered by local tourist company and it's unknown if they will still operate next year. If international flights stop it's not clear if any civilian flights with operate there. On top of that the town responsible for the trail is trying to increase the number of tourists using it. A road linking Sisimut and Kagerlussuag is under construction. Currently it's only an ATV track but plans for proper road exist. So it's possible that completing the trail will be soon significantly more complicated, there will be more traffic there or that things will stay the same for couple more years. No one knows.
Basic details can be found here: https://arcticcircletrail.gl/
General info: It's a beautiful, 160-210 km trail. Lots of wildlife, great views...
Getting there: Currently you can fly from Copenhagen directly to Kangerlussuaq or to Sisimut through Nuuk. Sisimut offers additional connections with a ferry. Only one flight a week to/from Kangerlussuaq at the moment (on Wednesdays). Other connections and local flights exists as well.
Hiking time: The official estimate is 8-10 days. That's a lot for 160km so I wasn't sure what to think about it. As you can expect it's exaggerated. It took us 5.5 days to finish the part between Sisimut and Kangerlussuaq and we had plenty of time to rest, wait for better weather and stop at beaches. 7 days should be plenty. 8 is more than enough. That being said the terrain is difficult. There's a lot of mud and streams so you have to constantly look for best places to cross them without getting all wet. You will have to cross a river couple of times. It does slow you down so it will take more time than similar trails in easier terrain (for example West Highland Way is 154km and took me only 4 days).
Markings: the trail is pretty hard to follow. The current trail, old version of the tail, ATV road and official GPS track all run in parallel over some portion of the trail. Sometimes all of it overlaps, sometimes nothing does. It's easy to start following the very visible ATV road and miss the place where the trail diverts. When the terrain gets wet the trail splits into many different path that end nowhere. I would recommend following the GPS track.
Water: plenty but I would recommend filtering
Direction: 95% of people go from Kangerlussuaq to Sisimut. No idea why. We went the opposite way and passed most people over 2 days (because everyone comes in the same plane). Plenty of benefits of starting in Sisimut which I will mention in other sections.
Supplies: There's a big, well equipped outdoor store in Sisimut. It closes on 17:00 but if you're flight arrives later you can order online and ask them to leave your things behind the store. There are also couple of supermarkets there. There's a smaller outdoor store in Kangerlussuaq and one supermarket there (everything closes at 17:00). Of course nothing is available on the trail itself.
Remoteness: We saw about 30 people on the trail. It was clear a lot of people arrived on the same plane and hiked quite close one group after another. For about 2 days after leaving Sisimut we've seen hunters riding ATVs on the road parallel to the trail. Few ATVs left Kangarlussuaq so we couldn't see them later. No cell phone coverage on most of the trail.
Southern route: There's an alternative path that avoids the ATV road. It has some stone markings but not a clear path. We were told it can take up to 5 days just to finish the section where southern path diverges from the original trail. What would mean it takes about 3 days more in total than the northern route.
Huts: You will pass a hut or two every day. The huts are very different, from very simple ones fitting only 2 people to bigger ones, with multiple separate rooms. All of them have kerosene heaters but none have fuel. We spend 5 nights on the trail and we had one hut completely to ourselves, one hut we shared with one more person and we had a full room to ourselves in another one. The other nights we camped because the huts were full or we reached them to early in the day. As I said, most people from for Kangerlussuat to Sisimut and leave on the same day. Following this plan it will be hard to find room in any of the huts.
Canoes: Part of the trail traverses a 20km lake. This part can be done in canoe or on foot, bordering the lake. Canoes can be found at one of the huts at either end of the lake. Closer the Sisimut there's a big hut (Canoe centre) with 3 big rooms. If you're late all the canoes will be at Canoe Centre and you will have to wait for someone to cross the lake in other direction to get a canoe. Since 95% of people are going the same way it can take a lot of time. Starting the route in Sisimut pretty much guarantees you will have a canoe available.
Mosquitoes: we hiked in the second half of August and didn't have any issues with them. Apparently colder weather during the summer killed all of them and there's usually more of them on the trail.
Extension: Hiking from Sisimut you can skip Kangerlussuaq entirely and follow a trail over the mountains directly to the glacier. The route is really nice and well marked. It's not as remote (you will have some cellphone coverage and there's a road nearby) but there's still plenty of wildlife and great views. You can also go down do Kangerlussuaq, recharge and start the trail from there. You get 300 days of sunshine per year in Kangerlussuaq so weather on this part of the trail should be significantly better. You can camp right next to the glacier but it will be a bit colder during the night. Trips to the glacier and ice cap are organized from the town. Some people take them and stay at the glacier so they hike from the Glacier directly to Sisimut. If you go to the glacier you will have to hike back to the town on your own. This extension adds 50 km to the trail.
