Marble Mountain Professional Review and Guide
"The trip up Marble Mountain is an intermediate-level ride with advanced-level views. The 13.2-mile route is a reverse lollipop configuration, with the sweeter part on the stick!The out-and-back sections leads to the top of Marble Mountain, which, on a clear day, provides views of nearby Mt. St. Helens, and also Mt. Rainier, Mt. Adams, Mt. Hood, and other high Cascades peaks and ridgelines.
You've got to believe what I'm telling you here; on the day of research it was cloudy enough that I was only able to see the lower part of Mt. St. Helens to the north. On a clear day, it dominates the views along the way. An added bonus on this ride is that you both begin and end with a descent! Some of the best non-singletrack riding in the area, with some of the best views."