Plano Mall Tunnels
After a couple false starts in finding interesting places earlier in the afternoon, Turtle suggested that we check out some tunnels we had both heard of by the mall in Plano.  I had visited the mall many, many times when I lived near there, but somehow never noticed these.  As it turned out, they held a lot of surprises.

Even though he's in the foreground, Turtle is dwarfed by the scale of the three big tunnels. 

This was the first time I put my "laser tape measure" to any real use on an expedition, and I found that the big tunnel was 37' across and 15' high at the center.

The tunnel really isn't all that long (note the light at the opposite end), but it was delightfully explorable!

There were several tunnels like this that fed into the main one from the side.  This was the first one we checked out...

...which happened to open out into a 15' high room.  Turtle was able to climb up rungs on the wall (out the frame to the left) to get to the smaller tunnel he's sitting in, but you would have to be Spider-man to get to the larger tunnel on the right.  It was a sheer wall leading up to that.

Next, we went into another side tunnel in the large tunnel to the right.

This one ended just beyond this spot in the smaller tunnel on the right.

At the end (and at a another point along the way) we reached grates in the mall parking lot.

Once we finished that tunnel, we returned to the big one to see what was further along.

There were several large stones like these.  No, not the ones in Turtle's pants!

In addition to this evidence of the force of water, there were signs that the water level reached as high as 10' above the bottom, as there were places where debris had become trapped on protrusions from the walls.

A little further along we found three parallel 6' culverts that were filled with some pretty good graffiti (e.g., humorous versions of the typical satanic clichés).

Two of these tunnels continued upstream and uphill for a bit...

...and had a few side exits where we were able to peak out and get a GPS reading.

From these we could tell we were approaching highway 75, but a little further ahead it became obvious that we were passing beneath it from the sound of the traffic projected into the smaller pipes from the curbside drains.

Continue to Part II