Only one lane, deep manhole covers at the edge, a lot of traffic, a bus without lights overtook us by changing between the demarcation pylons to the other lane and then merging back into our lane.
The tunnel is just over 2 km long. In general, tunnels are dangerous for cyclists, so tunnels are always recommended to drive through with a car. I was traveling with a group of bikes at the time, so the access was closed to vehicles.
Clean street. Well lit. The tunnel connects the two provinces of Van and Bitlis. There are many mountains in the area, so the tunnel is unavoidable.
Tunnel looked pretty sketchy. We avoided it by taking the old road over the pass. It's 200hm extra but you will have no traffic at all and some nice mountain views!