
The Kristinartindar hiking trail is the best kind of trail, an ascent, and one of the most famous hikes in Skaftafell National Park. Named after Mount Kristínartindar, a beautiful peak rising to 1126 m and surrounded by several glaciers.
This is a technically challenging hike, and quite a long one too, almost 18 km long (17.9 km), so you can count 6 to 8 hours to make the return trip (Camping - Sjonarnipa - Glama - Kristinartindar - Sjonarsker - Camping). The elevation will also represent a full kilometer, so you'll definitely feel that in your legs.
For reference, Vatnajökull National Park gives the S4 as roughly 17.9 km, 6 to 8 hours and 1215 m of elevation gain, rated "difficult", so it is only for experienced hikers. The trail starts in front of Skaftafellsstofa (the visitor centre). The first part of the route is the same as the Svartifoss hike: you can pass by the waterfall before continuing to Sjónarsker, but the shortest way is to cross the river by the footbridge near Magnúsarfoss.
If you do the loop in the other direction (going up via Sjónarsker), the park advises that on the way back, once you are on the ridge again, you take the left-hand path down to Gláma, then Sjónarnípa, and finally return to the visitor centre via Austurbrekkur.
On the map the hike overlaps the S3 “Skaftafellsheiði” trail, but this one is officially referenced as S4 and incorporates the Kristínartindar ascent.
When to hike it: the Kristínartindar trail is usually closed from the beginning of spring, and sometimes until June, because of the thaw, and there is no alternative route to the summit. The hike is therefore best done in summer (June to August, with long daylight hours) and is not recommended in winter. Check at the Skaftafell visitor center before setting off.

The circuit starts at the Tourist Center, very close to the campsite. The elevation on this trail is significant, so don't even think about climbing Kristínartindar in bad weather. The trail is also usually closed in early spring, sometimes until June, because of the thaw (check with the Skaftafell visitor center).
The S4 loop can be done in both directions, but we recommend counterclockwise.
This means starting out heading towards the Sjonarnipa viewpoint. After about an hour through moorland and birch forest, you will come across the breathtaking Sjonarnipa viewpoint with its panorama of the Skaftafelljokull glacier flowing into the sea.
This first section of the hike is not much of a challenge, with about 280 m of elevation between the car park and Sjonarnipa... But that's the end of easy-mode, from here on out, things get hard.

The second leg continues for 1 hour north to the Glama viewpoint, climbing the glacier to reach an altitude of 650 m. This viewpoint is where the two peaks of Kristinartindar are revealed in all their splendour.
Take the first stony path to ascend the smallest peak (980 m), then follow it back down between the two, and complete the final ascent of the highest peak. The ascent is not too technical, but it is demanding, totalling about 1.5 hours from Glama.
Safety points for the final climb: the last section is steep, with scree and loose stones, and a few exposed spots. At one point the trail almost disappears and seems to cross a short exposed section: it is better to go around a few metres higher up. On the last stretch before the ridge the path is not marked, and it is easy to start climbing too early, which means losing time on difficult dead-end terrain, so slow down and look carefully for the route. Once on the ridge, keep your distance from the edge, as a gust of wind can be dangerous.
The panoramic view from the summit is spectacular with mountains, glacier tongues, and above all the endless expanse of the desert sands as far as the eye can see. Finish the loop going down the same stony path you came up before heading west towards a beautiful meadow.
Worth knowing for the summit: in clear weather the view also takes in Morsárfoss, the highest waterfall in Iceland (228 m), fed by the Morsárjökull glacier. Bring binoculars or a telephoto lens, as it is quite far away. With good visibility you can also pick out Hvannadalshnúkur, the highest peak in the country, and follow the river flowing from the glacier tongue all the way to the sea.
After ascending Kristinartindar, the rest of the trail is all downhill. That is of course unless you have the stamina to extend the hike to Nyrðrihnukur to admire the beautiful viewpoint, adding another 30 minutes from Kristinartindar.
It takes another 1.5 hours to reach the Sjornasker viewpoint and its magnificent panorama over the Morsardalur valley to the west, then 30 minutes to make it back to the car park.

Photo credit Kristinartindar : defender06@fotolia