Geocaching basics

Afton State Park

10-11 a.m. Friday

Learn your way around the woods with a global positioning unit at the same time you discover hidden treasure. This is a beginner program. A limited number of GPS units can be checked out, or bring your own. (651-231-6968, mndnr.gov)

Scavenger hunt

Interstate State Park

1-3 p.m. Friday

Scavengers will be charged with resolving this question: Which animals value acorns the way humans value gold? Pick up your instructions at the visitor center and start your 20-minute search for clues leading to treasure. The route is less than a half-mile. Wear good hiking shoes. (651-465-5711, mndnr.gov)

Hidden hike

Whitewater State Park

1-3 p.m. Friday

Learn a few park secrets on this 3 ½-mile hike that will show you sites hidden from even the most-experienced visitor. You'll be off-trail and venture into a rarely used area. Warm clothes, good hiking shoes and cameras are recommended. No dogs. (1-507-312-2300, mndnr.gov)

Fall festival

Lake Shetek State Park

1-3:30 p.m. Saturday

Decorate a pumpkin, paint your face, enjoy a beverage, and make a s'more. Then jump into the biggest leaf pile in Minnesota. The festival will take place in the Zuya Group Center. (1-507-763-3256, mndnr.gov)

About raptors

Gooseberry Falls State Park

2-3:30 p.m. Sunday

• The peregrine falcon is the fastest bird in the world. Once a threatened species, the peregrine falcons are nesting again on Minnesota's North Shore. Hear the story of the falcon's recovery from Jackie Fallon with the Midwest Peregrine Society, and see one up close. (1-218-595-7100, mndnr.gov)

Lowry Nature Center

2-4 p.m. Sunday

• Meet and learn about captive raptors. Cameras welcome. Drop in anytime. The program is for all ages. (763-694-7650, threeriversparks.org)

Coon Rapids Dam Regional Park

10 a.m.-noon Wednesday

• Learn how Minnesota birds of prey survive fall and winter. Cost is $5. Reservations required by Monday. Call 763-559-6700. (threeriversparks.org)

Full moon activity

Gale Woods Farm

6:30-8 p.m. Tuesday

• Journey through the park on a wagon ride lit by the moon. Explore the barn and hay maze, and enjoy a bonfire and s'mores. Cost is $6. Reserve a spot by Friday. Call 763-694-2001. (threeriversparks.org)

Sochacki Park

7:30-9 p.m. Wednesday

• Adapt your senses and explore the natural world on a night hike. Dress for the weather and walking on uneven woodchip trails. (763-559-6746, threeriversparks.org)

Mountain biking

Murphy-Hanrehan Park Reserve

6-9:30 p.m. Monday

• Experience the rush of night racing on 10-14 miles of single-track trail. Mounted bike lights required. Cost is $12 to preregister; $15 the day of the race. Call 763-559-6700 to preregister. Open to ages 14 and older. Races rotate among Elm Creek Park Reserve, Lake Rebecca Park Reserve and Murphy-Hanrehan Park Reserve. (threeriversparks.org)