This 2.5-mile-long tunnel originally had trains passing through it. After the threat of war had abated, the train was used primarily for transport of ferry passengers. A driver would come off the ferry, go up a ramp on the train tracks, and park the vehicle on a flatcar. That's what Ben did in 1975. Now, the supplies previously brought by the train are brought by truck, and the train only carries passengers, twice daily. Tourists can drive their vehicles straight through the tunnel.

Vehicles pay a toll to go eastbound while westbound (from a ferry) is free. The tunnel is one lane, and cars and trains take turns traveling through it. When a train is passing through, vehicles must wait in the staging areas on either end.

For most of the drive you cannot see the exit - just walls. Except for a few emergency turnouts, the walls are never more than four feet from either side of the car. The walls are rough, faceted rock all the way, except for patches that hang beneath small underground streams. Those patches are covered with blunt, dirty icicles creeping over each other and down to the metal floor.