Extend the Story - Add a Room

Before leaving town, Jezirea stocked up for the journey, buying rations for a few days and various equipment she might need while spelunking - lots of rope, and a lantern with a hefty supply of oil to fuel it.
The book had indicated where the base of operations was for the mines, so she figured that would be the best place to start looking. She knew full well that without knowing the exact location of the golem that this search could take weeks, and she could possibly come away empty handed, but the best offense in this case was a carefully executed plan.
She headed for the mine site which was a half hour trek from the village. It was abandoned and run down, as she expected. It looked like the site had been picked clean of building materials and tools after it fell to disuse, and now there was nothing left but a few ramshackle, rotting buildings, slowly being taken over by the surrounding forest, and one very large hole in the ground. She surveyed the mine site, and found that there were three tunnels leading away from the main dig site. So which one would she start with?

Middle tunnel.