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AWG Ape Cave Field Trip

This is not a GSOC field trip. Please join the Association of Women Geologists for a hike through Lower Ape Cave on the south side of Mt. St. Helens, the third longest lava tube cave in the lower 48 states.  The cave formed within a basalt flow nearly 2000 years ago.  As a group, we'll go through the easier Lower Cave (1.6 miles RT within the cave), but more adventurous people may choose to follow that with a hike up the more challenging -- but more interesting -- Upper Cave (1.5 mile one way in the cave, then 1.3 mile surface trail back down), which includes a lava falls ascent.  The entrance is midway in the cave, so you can choose to do one or the other or both, but as a group we’ll hike the Lower Cave.  Afterward, weather permitting, we may wish to continue up FS Road 83 to do a short loop hike at Lava Canyon.  (If you wish to continue up the trail, please be advised that the suspension bridge is out.)  Please let Marcia Knadle ( know if you plan to come.

Location:  Ape Cave (south side of Mt. St. Helens)

Date:  Saturday September 28, 2019

Time:  10 am -- meet in the Ape Headquarters parking lot (allow about an hour from Woodland, WA and about 1.5 hours from downtown Portland)

Cost: Nothing.  This is because you'll be responsible for your transport, lunch, and any lodging.  If you don’t have an annual or lifetime National Lands pass (the erstwhile National Parks pass) for your vehicle (hang from the rearview mirror or place on your dashboard), you’ll need to pay $5 for parking.  It’s NOT available at the parking area, but you can pick the day pass up at the Lone Fir Resort in Cougar.

Carpooling:  If you’re coming from the north, please let Marcia know if you want to ride with someone or, better yet, are willing to drive.  If you’re coming from the Portland area, please contact Erin Dunbar ( with the same information.  If you wish to drive back north via Windy Ridge on the east side of Mt. Saint Helens on Sunday, please contact Marcia.  The Windy Ridge route is a full day's drive, so plan to stay somewhere near Ape Cave on Saturday night and make this drive on Sunday.  However, it's probably not worth doing in low clouds or rain.  Also, the road gets pretty narrow in places, so taking a large vehicle is not advised.

Lodging:  Those coming from the north will probably wish to stay somewhere near Ape Cave (Marcia plans to stay at a motel in Woodland Friday night).  Please see page 3 for motel, B&B, and camping options in Woodland and Cougar..   

Clothing:  The cave is a cool 42 degrees, so you'll need warm clothes and gloves.  You may also want to wear a rain jacket, since stalactites tend to be drippy.  (If we get a lot of rain this  month, it could be downright wet.)  You will also need at least two robust light sources, three if you're really paranoid (your phone's flashlight isn't strong enough to count).  Sturdy shoes will likely be adequate for the Lower Cave, preferably waterproof, since there may be puddles.  However, for the Upper Cave, you'll need hiking boots that protect your ankles, as well as good gloves -- you'll be climbing through rocks.  Since you'll need to use your hands through the Upper Cave, you may wish to have a headlamp.  The same goes for crawling to the very end of the Lower Cave.  Please take precautions to avoid spreading white-nose bat syndrome (see below).

Required paperwork:  You will need to sign a liability release form.  You may fill this out, scan it, and email it back to Marcia, or just bring it with you when you come.  We'll also bring blank ones for you to sign at the parking lot.

Please note that if you went into the Oregon Caves on last year's AWG-PNW field trip or have been in another cave, you will need to be careful NOT to wear anything you wore in one of those caves unless it's been properly cleaned (see below).  This includes boots.  This is to protect the bats from white-nose bat syndrome.

Save Our Bats Instructions

Save Our Bats Instructions