The third trip was in two parts: a scouting trip by me, Danarchy, Slim Jim, Tourettes, and Fuzzo, and a full exploration later on by Jim and me.

It was winter again, and cold as hell. In the time since we'd last explored, the "Mill Ruins Park" had progressed considerably. The tailrace tunnels were all barred off with big metal gates, there were educational signs posted, and the Cataract Tailrace was prepared to start gushing water again as it had back at the turn of the previous century, when hydroelectric power was as good as it got.

Fortunately, they had not diverted the water just yet, because the way we got in was through a gap beneath the Cataract gate.

On the scout trip, we once again explored all the dry-land portions of the tunnels. On the return trip, Jim and I went further.

Using large sheets of foam insulation sheets as makeshift rafts and our hands as paddles, Jim and I cautiously, precariously, rafted out into the flooded tailrace tunnel system. The water was stinking and frigid and at least six feet deep. It consisted of both runoff water from drains and of sewage from sewer lines that for decades have dumped into the tailraces when overloaded.

The rafts almost capsized every time we shifted our centers of balance. It seemed a forgone conclusion that one or both of us would wind up falling in, but we pressed on regardless, hoping to see as much as possible before being dunked.

The rafts allowed us to reach entirely new tailrace tunnels, some of which were flooded, others of which were dry. Where there was a "beach" of mud, we'd paddle into it at full speed and slide up as far we could onto land. Much more difficult were the places where there was only a cement ledge a few feet out of the water; I'm still amazed that we were able to get off of and onto our rafts in those situations without taking the icy plunge into the water.

The deepest parts of the tailraces, accessible only by raft, were the most interesting: there were plenty of ancient brick structures, rusted-out pipes and machinery, and odd caverns and caves to explore. And explore we did.

Hours later, we'd checked out every accessible part of the interconnected maze of flooded tunnels, and although we were largely covered in mud, and our arms and feet were soaked, neither one of us had tipped our foam rafts over. We docked our trusty boats and got back outside, where the heavy snow that had just begun to fall covered our exit wonderfully.

These days, the tailraces are securely locked up. In the shadow of the Stone Arch Bridge, river water cascades once again from the mouth of a tailrace tunnel that is the only remnant of a long demolished mill. A park with an emphasis on the historical significance and archeological remnants of the Mill District is underway and seems nearly complete. I've read that they plan on giving guided tours of small segments of one of the tailrace tunnels.

Obviously, we'd be happier if the whole site had stayed buried, and a "secret." It was awesome while we were among the tiny number of people who were able to appreciate the ruins of Minneapolis' past. However, if we had to lose our exploration grounds, I guess that it's pretty neat that the site at least gives the poor bastards of the general public a chance to appreciate a tiny part of what only us tunnel rats could enjoy before. Beats the crap out of building condos, a mall, or a golf course over the place, anyway.