Sunday 9/29/2002, Trish and I walked the Iron Goat Trail. It's also part of the Rails-to-Trails system. Unlike Iron Horse, there was more shade and more historical information but it's shorter (much shorter!).

If you go left from where we started, there's an old tunnel. A sign outside proclaims "Goodbye Switchbacks!" It reads "As you stand in front of this tunnel, imagine being a rock miner who worked seven days a week for three years. Or an engineer who surveyed the line so accurately that when the tunnel was holed through, the two sides were almost perfectly aligned. Imagine being a train engineer who was thankful to avoid the twelve miles of switchbacks but apprehensive about the tunnel which trapped exhaust smoke from the coal-fired engines. The 2.6 mile Cascade Tunnel was completed in 1900 and connected Wellington and Cascade Tunnel Station on the east side of the Cascade Mountains." You can't actually go very far into the tunnel because it has collapsed - water coming down through ceiling, rocks strewn about, and then shortly past that, the ceiling and the mountain above it on the floor.
 
Avalanches are a major problem in the Cascades so they built snowsheds to re-route the snow across the tracks (and train) and down the other side. That's Trish standing in front of the beginning of the snowshed. As you can see from the second pic, it didn't always work. Even though this snowshed was reinforced cement, there was an avalanche sufficient to collapse the other end of it. You can read about the horrible loss of life on the web site. As you walk along the inside of the snow shed, there are spikes and other artifacts on display. It's chilly under there and flat-out cold in the tunnels.
 
The first pic shows trees downed in that avalanche. You can barely make out the end corner of the snowshed in the upper right quadrant of the picture. The second shows the back end of a tunnel closed by an avalanche. Don't know why I didn't take a pic of the front of the tunnel.
From part of the trail, you can see the new tunnel far below that's still in use today.