Description:Mt. St. Helens is unquestionably one of our region�s most iconic, well-known, and  powerful attractions. Approaching Mt. St. Helens National Volcanic Monument from the south, locals and visitors to Portland have the unique opportunity to enjoy both spelunking at the Ape Cave, the largest continuous lava tube in the continental United States, as well as exploring the visitor centers in and around the  Blast Zone. Stopping to take scenic photos along the way, your naturalist will present dramatic evid...