The trail is crushed gravel. The east trail has little change in elevation. The tunnel does not have lighting. Headlamps and/or high powered flashlights are strongly recommended. It stays cool inside the tunnel at roughly 55-65 degrees Fahrenheit depending on the time of year. Please note that water drips from the top and sides of the tunnel interior constantly, creating ruts and puddles on the interior of the tunnel trail path and is a natural occurrence.

Here’s trail slope and grade information:

East Trail to East Tunnel Entrance
Length 3,346 ft. (0.63 miles) net change in elevation +37 feet, max. grade 5.3% for 150 feet, most of the rest of the east trail is < 1.6% ; avg. 1.5%

Length of Tunnel
4,273 feet; change in elevation +55 feet; average grade 1.3%

West Trail to West Tunnel Entrance
Length 4,279 feet; change in elevation +175 feet; grades range from -17% to +19% for lengths of 150+ feet with grades over 5% for a majority of the trail; average grade is 6.5%; max grade 19%. One section includes a concrete mat stream crossing that may have water flowing over it during or shortly after rainstorms.

Trail width is 10 ft.
Cross Slope 1-2% for the entire trail.
East Trailhead to West Trailhead: 2.25 miles.