F839 (Leirdalsheiðarvegur) is a demanding drive located on the north coast of Iceland. It's only suitable for 4x4 vehicles with very high ground clearance: along the way there are a few small fords to cross.
The road runs south-north from Grenivík towards Hvalvatnsfjörður. It’s 27km long through the valley Austurádalur. It is a rough and challenging road only for a 4 wheel drive vehicle with high clearance. The track is pretty bad, it's not rolling with a lot of big rocks. Expect large potholes, many ruts and large boulders on their surface. Driving in a small passenger car is simply and plainly irresponsible and can be very dangerous. It has some steep sections. It’s one of the famous F Roads of the country.
The road is surrounded by lunar landscapes and is pretty bumpy. It’s only open during the summer months, usually between late June and early September. Expect to be alone, this track is not very busy. It is not recommended to drive unaccompanied. In case of a breakdown, there is very little in the way of passing traffic or inhabitants around, and no cell phone service in parts. The drive offers breathtaking landscapes.
There are a few small fords to cross but not very deep (maximum of about 30cm high). Crossing big rivers requires a bit of experience. Do not attempt to cross with one car, or during heavy rain. It can be treacherous if the water level rises due to lots of rain and warm weather. Only well equipped jeeps and larger vehicles are able to cross the rivers. Please do not attempt to cross this river on a small jeep. In case you get stuck in the river, call 112. Always check the river to ensure that it's not too deep. Rivers that can change rapidly with rain or change in heat. This road is amazing by day, but can be dangerous during the dark night. Rental car insurance does not cover damages from water, including any damage caused by crossing rivers.