If you love biking or hiking, Minnesota offers plenty of options. But what if your idea of fun is doing farm chores? In this era of industrial agriculture, it's not easy to find a cow to milk. But not impossible.

Nor is it hard to look out over treetops, examine billion-year-old geologic formations, wander through the woods in the dark, or take your kids fishing even if you haven't threaded a worm since you were their age. All of these activities are within driving distance of the Twin Cities.

Minnesota parks offer opportunities for practically any recreational activity you might think of, from horseback riding to geocaching to mushroom hunting. Then there are activities you might not have thought of — adventures ideal for families, beginners, or anyone game for an unusual experience.

Climb a tower

If gazing 20 miles in every direction sounds fun, climb a fire tower. From the 1930s to the 1970s, park rangers used towers to scan forests for smoke. These days, that's done from aircraft, but five state parks keep towers open to the public. It means climbing 100 feet of stairs, said lead naturalist Connie Cox at Itasca State Park, but the reward is a spectacular panoramic view.

"They'll see the tops of our towering pine trees — what we call the super canopy — poking out of the [other] treetops: oak, maple, birch, aspen," Cox said of the fire tower at Itasca. "Immediately below are Allen and Kasey lakes. In the summer, a pair of trumpeter swans is usually nesting in one or the other lake. Sometimes visitors can look down and see these giant white swans."

Ancient geology

If you want to explore Minnesota's very distant history, head to Interstate State Park in Taylors Falls and take a guided tour of billion-year-old geological formations. The park features potholes carved by glaciers — some the size of paint cans, some big enough to hold a school bus, one you walk down into, partially underground. They're believed to be the densest concentration of such potholes on the planet.

"It's kind of like entering a whole different world," said naturalist Jenni Webster.

The big one is called the "Bake Oven" because it resembles an old-fashioned oven, but that's kind of a misnomer, because the dense rock keeps the holes cool ("a nice treat when it's 90 degrees," Webster said). The rock began to form 1.1 billion years ago, when geological forces tore a rift in the continent that oozed lava for millions of years. A mere 10,000 years ago, spinning sand in whirlpools from melting glaciers drilled holes into rock so hard you'd normally need a diamond drill to cut it.

"It's a unique experience to reach out and touch something that's [a billion] years old," Webster said.

Your 'grandparents' farm'

Hey, what about those farm chores? On summer Saturday mornings, visitors to Gale Woods Farm in Minnetrista (threeriversparks.org/location/gale-woods-farm) "can milk a cow, help collect eggs, feed the sheep," said supervisor Tim Reese.

Gale Woods is a small but diversified working farm — with cattle, sheep, pigs, lambs, chickens, gardens and orchards — that sells its products onsite. A farm might not have seemed like an exotic destination a few generations ago, when more than half of Minnesotans lived on one. But now that the state's farm population has dwindled to less than 2 percent, "we're often called everybody's grandparents' farm," Reese said.

By the light of the moon

Feel like roaming around after dark without so much as a flashlight? You can do it by foot, canoe, kayak or stand-up paddleboard in Three Rivers parks (tinyurl.com/fullmoonoutings), each month on the night of the full moon. A naturalist will identify the creatures rustling around out there: raccoons, deer, fox, waterfowl, turkeys sleeping up in trees. Most are harmless, though a few are a bit creepy, like the female glowworms that deliberately blink in patterns that lure unsuspecting males of other species, then devour them.

Each month's full-moon program focuses on a specific creature — frogs, bats, moths — said naturalist Pauline Bold, who has conducted outings for more than 30 years, mostly at Richardson Nature Center in Bloomington. She helps people feel more comfortable in the dark. "We just teach them that there's nothing out here that's not here in the day — they're just more active at night." Bold's barred-owl call is so accurate that she can get one to fly over and perch in the trees above.

Her favorite walk is on June 9, when the group will observe swarms of fireflies. "We can't get people to leave; it's like they're watching Christmas lights out there — it's a magical, magical program."

You can do it

Fishing is just one of the skills you can brush up on (or learn from scratch) in the state parks' "I Can!" programs (mndnr.gov/ican). The naturalist-guided programs started in 2010 with camping and expanded to include fishing, canoeing, kayaking, rock climbing, mountain biking and archery.

They were developed after a survey showed fewer people were engaging in outdoor activities, said coordinator Eric Pelto. "One of the main barriers is that people just don't know how to recreate in the outdoors. We teach them entry-level skills so they can do it on their own — we provide the equipment and planning, and set them up for success."

Last year, the programs drew nearly 14,000 people (Pelto recommends registering early). Many have sent enthusiastic follow-up notes.

"Families will say, 'Hey, we just wanted to let you know that after the I Can Camp! program, we went out camping three more times that summer,' " Pelto said. "I think there's a lot of people that don't grow up camping or fishing or canoeing or kayaking or whatever, but maybe they want their kids to have those experiences. They don't want to fail at it; this gives them the confidence."

Katy Read • 612-673-4583

Activities at Minnesota Parks

Three Rivers Park District: threeriversparks.org/activities. For an activity search engine, see tinyurl.com/3riversactivities.

Minnesota State Parks: dnr.state.mn.us/state_parks/events.

Many activities are free or have a minimal cost; check the websites for dates, prices, age requirements and other information.