This is an Iceland highlands driving guide written from the driver's seat, not from a brochure. The interior is the empty middle of the country: no fuel, no shops, patchy phone signal, gravel tracks that open for about ten weeks a year. It is genuinely worth seeing. It is also the place where cheap holidays turn into five-figure repair bills. Here is what the three main crossings are actually like, what the vehicle and insurance rules really say, how to plan fuel and supplies, and why most people doing the Ring Road in a week should leave the Highlands for the next trip.
The interior is a cold desert. Black sand, old lava, glacial rivers, and long stretches where nothing grows at all. There are no towns up there. No pumps, no shops, no garage, no ambulance ten minutes away. On Sprengisandur you can drive for two hours and meet four cars.
Most of the plateau sits between 400 and 800 m. Snow lies in the hollows into July. Weather moves fast and sideways: a calm morning at Gullfoss can be a gritty 20 m/s at Hveravellir by lunchtime.
The F in front of a number is a legal marker, not a difficulty rating. F35, F26, F208, F225: a 4x4 is required by law, and that means real four-wheel drive, not a raised 2WD crossover with plastic cladding.
Rental insurance follows the same line. Take a 2WD past the F sign and every policy on your contract is void from that point: CDW, SCDW, gravel, sand and ash. You are then personally liable for the entire car.
Water damage is never covered. No policy in Iceland covers it, in any vehicle, at any excess. Stall in a ford, pull water into the intake, and you buy the engine. That bill runs into five figures in EUR and all of it is yours.
Driving off the marked track is illegal everywhere in Iceland and the fines are heavy. Wheel scars in highland moss stay visible for decades. Read your own rental contract too: many companies ban specific F-roads even in a proper 4x4. The detail is in our F-road rules page.
Season matters as much as the vehicle. F-roads typically open between mid-June and early July and close again in September or October. The road authority sets the dates each year based on snowmelt and storm damage, so last summer's dates tell you nothing about this one. See when F-roads open for how the openings usually roll out.
Kjolur runs from Gullfoss north between the Langjokull and Hofsjokull ice caps and comes down to Route 1 near Blonduos. Around 200 km, most of it signed F35.
It is the softest of the three. The main line is bridged, which is why scheduled highland buses run it in summer and why it usually opens first. That does not make it a normal road. Still gravel, still washboard, still 4x4-only by law, still no fuel and no services.
Worth stopping for: Hveravellir hot spring and hut roughly halfway, and Kerlingarfjoll on the F347 spur, which is the best single reason to be on this road. Budget 5-7 hours for the crossing with stops, more if the wind gets up. Do not start it at 6 pm.
F26 crosses the middle of the country between Hofsjokull and Vatnajokull, from the Hrauneyjar area in the south to Bardardalur in the north, dropping out near Godafoss. Roughly 200 km of gravel with almost nothing in between. The Nyidalur hut sits about halfway and is the only real shelter on the route.
This is the long one and it opens late, often not until early July. The big rivers on the main line are bridged, but there are fords that change with the melt, and the surface ranges from washboard to soft sand. Treat every crossing as unknown even if a blog said it was ankle-deep last August.
Honest version: Sprengisandur is grey, flat and tiring compared with the south coast or the east fjords. People drive it to have driven it. If you want views per hour, it is the worst value road in the country. If you want emptiness, nothing else comes close.
Fjallabak is the rhyolite country behind Hekla and Myrdalsjokull, and it is where Ring Road travellers actually end up if they go highland at all. Landmannalaugar is the target.
There is a ford at the entrance to the Landmannalaugar campsite. Most rental contracts do not permit it and most drivers should not attempt it. Park on the near side and walk over the footbridge. That is what the parking area is there for.
On fords generally: never go first if another vehicle is about to cross, wade it before you drive it, cross in the morning rather than after a warm afternoon, keep steady low-gear momentum, and never open the throttle mid-river. Our river crossings guide goes deeper. The short rule: if you are standing on the bank asking whether the car will make it, the answer is no.
Fuel first. Fill to the top at the last station before you climb. In the south that is the Hella, Hvolsvollur or Hrauneyjar side; in the north, Varmahlid, Blonduos or the Myvatn area. There is nothing in between.
Then do the range math honestly. A heavy 4x4 on loose gravel, in low gear, into wind, burns 30-50% more than the same car cruising Route 1. Assume your usable range is about two thirds of the brochure figure, and turn back at half a tank if you have not reached the far side.
Rough money, high summer. A properly highland-capable 4x4 of the Land Cruiser or Defender class rents for something like EUR 200-350 a day before fuel. The small 4x4 category at EUR 120-180 is often contractually barred from the harder routes, so read the terms before you assume it covers you. A guided super jeep day trip to Landmannalaugar or Thorsmork sits roughly in the EUR 200-400 per person range, and the highland bus is cheaper again. All of it moves with season and demand.
The arithmetic falls out of that. Two people wanting one day in Landmannalaugar: the bus or a guided activity wins on cost and removes your insurance exposure completely. Four people with camping gear and three or four days in the interior: self-drive wins, and you can compare rental cars by what each company actually permits on F-roads rather than by headline price.
Thorsmork is the clean example. F249 crosses the Krossa, which moves its channel through the day, and effectively no rental company allows it. Take the bus. The drivers who ignore this are the ones being winched out at dinner time.
Route 1 is about 1,322 km, fully paved, and not an F-road. A 2WD handles it in summer without drama, and nearly everything people come for sits close to it: Seljalandsfoss, Reynisfjara, Jokulsarlon, the east fjords, Myvatn. If you are only doing the ring, do you need a 4x4 answers that question in one page, and a 7-day Ring Road itinerary is already tight without adding gravel.
Adding Sprengisandur to a week costs a full day and real tyre risk for scenery that is deliberately empty. With seven days, skip it. With ten to fourteen days, and some gravel driving already behind you, Kjolur or a Landmannalaugar run makes sense.
Turn around, without arguing with yourself, when any of these is true:
Nobody regrets turning back at four in the afternoon. Plenty of people regret the other choice, usually while paying for an engine.
Yes. A 4x4 is a legal requirement on every F-road, and taking a 2WD onto one voids your rental insurance entirely, leaving you liable for the whole vehicle. The Ring Road itself is a different matter: it is paved and a 2WD is fine on it in summer.
Typically somewhere between mid-June and early July, closing again in September or October. Kjolur usually opens first and Sprengisandur last. The road authority sets the dates each year based on snowmelt and damage, so check road.is or umferdin.is rather than last year's dates.
It is the gentlest of the three. The main line is bridged, summer buses run it, and there is no major river crossing on the standard route. It is still gravel, still washboard, still 4x4-only by law, and still has no fuel for around 200 km.
Only if your contract allows that road, and even then water damage is never covered by any insurance policy in Iceland. Wade the ford before driving it, cross in the morning when meltwater is lower, and turn back if you are unsure. Conditions change daily, sometimes within a single afternoon.
No. Fill up and stock up at the highland edge in whichever direction you are going, and carry food, water and warm clothing for one extra day. Expect a heavy 4x4 on gravel to burn 30-50% more than it does on Route 1.
Usually no. A week around the island is already full, and a Sprengisandur crossing costs a whole day plus real puncture risk. If you want a taste of the interior, take a guided day trip or the highland bus to Landmannalaugar and keep the rest of the schedule intact.