Log in

Mid-Valley Bicycle Club

Oregon's Island in the Sky: Geology Ride up Marys Peak

  • 07/16/2023
  • 10:00 AM - 2:00 PM
  • meet at large paved parking lot 3.7 mi up Marys Peak Rd
  • 9


Description: We'll ride from the starting point to the top of Marys Peak, with stops along the way to view and discuss the geological structure of Marys Peak and how it relates to other aspects of the natural and cultural history of the Pacific Northwest. 

It will be ~  14 miles round trip to the top of Marys Peak and back to the parking lot with about 2000 feet of elevation gain. 

Surface: Most of the ride is paved, but the first stop (to a rock quarry) includes 1/4 mile of gravel road, and the last stop (to the top of the peak) is along a 1/2 mile gravel road. Riders with tires not suitable for gravel will want to lock their bikes and walk those stretches. 

Pace: This will be a slow pace and include educational time at each of the four stops. So bring a lunch if you wish, and don't expect to arrive back at the starting point before 2:00 PM.

Education Leader: Dr. Robert J. (Bob) Lillie is a writer, illustrator, and national park ranger specializing in communicating park landscapes and their deeper meanings to the public. He was a Professor of Geosciences at Oregon State University from 1984 to 2011 and is a Certified Interpretive Guide and Oregon Master Naturalist. Bob has served as a seasonal park ranger at Crater Lake, Yellowstone, John Day Fossil Beds and other national parks, and he has written and illustrated several books available in parks and museums in the Pacific Northwest. Bob has done Cycle Oregon several times, as well as cycling excursions in the Alps, Scandinavia, and the British Isles.

What We'll Learn: At 4,097 feet Marys Peak towers over other mountains in the Oregon Coast Range. A ride up Marys Peak is an opportunity to experience the geological history of the Oregon Coast Range by observing rock quarries and road cuts along the way. The hard rock capping the peak sustains its great height and preserves Noble fir forests and subalpine meadows left over from the last ice age. Summit views of the Pacific Ocean to the west and Cascade Volcanoes to the east show how the Cascadia Subduction Zone has shaped the landscape of the Pacific Northwest, and reveal how we can prepare for future earthquakes. From volcanic eruptions on an ancient seafloor, to powerful forces between tectonic plates, to the durability of hard intrusive rock, a journey up Marys Peak is truly like visiting an "Island in the Sky."

Resources: One of Bob's books is titled: "Oregon's Island in the Sky: Geology Road Guide to Marys Peak" ( ). Each rider will be supplied a copy of the book and we'll refer to some of the illustrations at the educational stops. Riders can return the book after the ride; those who wish to keep the book may purchase it for $15 cash or check.

Upcoming events

  • No upcoming events

Donation goal

Powered by Wild Apricot Membership Software