What used to be a single night of costumed fun is now a full-blown holiday season more stuffed with activities than a bulging trick-or-treat bag.

We’re talking about Halloween, of course, and there’s so much going on that the family-friendly action starts long before Oct. 31. It’s the only way to fit it all in.

From costume parades and hayrides to corn mazes in the country and trick-or-treating Downtown — start now, and you just might get your fill of all these lively treats (and tricks) by the time the moon sets on All Hallow’s Eve.

Haunted Trail at DCHS: The Dane County Humane Society hosts its annual haunted trail to benefit its Four Lakes Wildlife Center, Saturdays Oct. 21 and 28. Ages 12 and under can attend from 2-5 p.m.; the trail gets a little bit spookier and better suited for older kids from 6-9 p.m., 5132 Voges Rd. Admission $10; $5 under age 12. Details at www.giveshelter.org.

Planetarium laser shows: Rock out to an eerie-cool Laser Show at the MMSD Planetarium Oct. 23-28. This planetarium fundraiser features shows ranging from the family-friendly “Legends of the Night Sky” to “Fright Light” and Pink Floyd’s “Dark Side of the Moon,” with lasers drawing animations on the dome to go with the music or story. Tickets $4 at the door or online at planetarium.madison.k12.wi.us/lasershows.

Downtown Madison Family Halloween: Halloween fun takes over Capitol Square and beyond in this big event, which offers trick-or-treating for kids 12 and under in 80 Downtown locations from 3-6 p.m. Wednesday, Oct. 25. And there’s much, much more:

Try hands-on crafts and other spooky delights at DreamBank, 1 N. Pinckney St.; the Madison Museum of Contemporary Art, 227 State St.; Madison Central Library, 201 W. Mifflin St.; and Capitol Kids, 8 S. Carroll St.

Be dazzled by a free “Mad Science Halloween Spooktacular” on the Rotunda Stage at Overture Center for the Arts, 201 State St., at 3 p.m., 4 p.m. or (with ASL interpretation) 5 p.m. Or take a Madison Parks Hay Ride around Capitol Square ($3/person; age 2 and under free; leaves every 20 minutes).

Come in costume to the Madison Children’s Museum, 100 N. Hamilton St.; or make a silly lumberjack beard and take a free, one-evening-only “haunted” cabin tour at the Wisconsin Historical Museum, 30 N. Carroll St.

More Downtown Madison Family Halloween events and details are at www.visitdowntownmadison.com

Halloween play date at Hilldale: The Madison Moms play date takes a Halloween twist at Hilldale shopping center from 10-11:30 a.m. Wednesday, Oct. 25 with crafts, activities and snacks, and a chance for the little ones to dress up. Located at the Green (in front of the Apple Store), 726 North Midvale Blvd. Free and open to the public, but advance registration requested on eventbrite; see www.hilldale.com.

Pumpkin Party! At Middleton Library: Celebrate a day off school by making your pumpkin masterpiece from 2-4 p.m. Thursday, Oct. 26. Bring your own pumpkin to paint and carve; limited supply of pumpkins also available. For all ages. Middleton Library, 7425 Hubbard Ave., Middleton. www.midlibrary.org

Bouncing Halloween Babies: Bring baby in costume for lap rhymes, songs, stories and fun designed for pre-walkers, starting at birth. 1-1:45 p.m. Thursday, Oct. 26 at Fitchburg Library, 5530 Lacy Rd., Fitchburg. Free. www.fitchburgwi.gov/822/Library

HOLLOWeen at the Cave: Wear your costume and trick or treat for gemstones in the candle-lit Cave of the Mounds in Blue Mounds from Oct. 26-29. Fall family activities include hayrides from the cave to Brigham County Park. Regular hours and admission costs apply: Weekend cave tours every 30 minutes from 9 a.m. to 5 p.m., with grounds open 9 a.m. to 6 p.m. Weekday tours on the hour from 10 a.m. to 4 p.m., with grounds open 9 a.m. to 5 p.m. $17.95 adults, $9.95 ages 4-12; under age 3 free with paid adult. 2975 Cave of the Mounds Road, Blue Mounds, www.caveofthemounds.com

Downtown Middleton Halloween Trick or Treat: Downtown Middleton will be decorated for fall during this eighth annual event sponsored by the Downtown Middleton Business Association from 11 a.m. to 2 p.m. Friday, Oct. 27. Stop by 34 participating shops to show off your costume and get a treat. Details at DowntownMiddleton.com

Special Effects: Monster Make-Up Class for Teens: Learn how to create scary makeup effects with a professional from 3-4 p.m. Friday, Oct. 27, at Middleton Library, 7425 Hubbard Ave., Middleton. Registration required at www.midlibrary.org. More information at 608- 827-7402.

Creatures of the Night at ALNC: Explore the Aldo Leopold Nature Center at its free “Creatures of the Night” Fall Fest held 5:30-7:30 p.m. Friday, Oct. 27. Come to the ALNC campus at 330 Femrite Drive, Monona, in costume to join the costume parade, conduct “sweet” science experiments, hear not-so-spooky stories in the haunted shack, roast marshmallows, and more. www.aldoleopoldnaturecenter.org

Family Fun Night: Haunted House!: Check out a spooky book or just have fun at the free family haunted house party at Goodman South Madison Library, 2222 S. Park St., 6:30-7:30 p.m. Friday, Oct. 27. Wear your costume and enjoy tricks, treats, and family-friendly frights. www.madisonpubliclibrary.org

Creepy Crawl and Trick or Treat: Mount Horeb’s Main Street is lit with luminaries for trick or treating from 6-9 p.m. Friday, Oct. 27. If you dare, also take the Creepy Crawl, a haunted hike on the Military Ridge Bike Trail, lit by carved pumpkins and lined with spooks and scares. Then visit the “spooky nook” with games, prizes and face painting. For all ages; less-scary Creepy Crawl experience from 6:20-6:50 p.m.; more scary experience from 7-8:15 p.m. $1 ages 2-12, $2 ages 13 and up. trollway.com/event/trick-treat-main-st-creepy-crawl/

Halloween Hustle: Slither into those running shoes and hop into a costume for the Halloween Hustle Kids Dash ($15/$20 day of race) beginning at 8:40 a.m. or the 5K ($40/$45 day of race) starting at 9 a.m. on Saturday, Oct. 28, at Olin Park, 1156 Olin-Turville Court. Kid Dashers receive a trick-or-treat bag, T-shirt and pumpkin at the finish line. Details and registration at halloween5Kmadison.com

Great Halloween Hunt: Fitchburg Public Library hosts its 10th annual Halloween party from 6-9:30 p.m. Saturday, Oct. 28. Enjoy crafts, games, a scavenger hunt, crafts and games, magician, balloon twisters and a screening of the 1951 film “Alice in Wonderland.” Free; Fitchburg Public Library, 5530 Lacy Rd., Fitchburg. www.fitchburgwi.gov.

Halloween at the Zoo: Wow the animals with your costume during the free Halloween at the Zoo, held from 9:30 a.m. to 3 p.m. Sunday, Oct. 29 at Henry Vilas Zoo, 702 S. Randall St. Activities include trick-or-treating, a bounce house, crafts, face painting, a costume contest and more. Enter the zoo’s pumpkin decorating contest the Friday before (details are at www.vilaszoo.org). More information at www.vilaszoo.org/hatz or 608-266-4732.

Trick or Treat on Monroe Street: Just a few blocks from the zoo, join Trick or Treat on Monroe Street from noon to 4 p.m. Sunday, Oct. 29. Look for the “Treat Stop” signs in the windows of businesses along the 1500-3500 blocks of Monroe St. www.monroestreetmadison.com

Baby’s First Halloween: Madison Children’s Museum hosts a special party for its youngest visitors. Visit a photo booth, try out activities for kids under age 1, and dance to Halloween music by Ken Lonnquist and Dave Adler. Free with $8 museum admission. 9:30-11 a.m. Oct. 31, Madison Children’s Museum, 100 N. Hamilton St. www.madisonchildrensmuseum.org

Trick or Treat hours: The main event! Recommended hours for trick or treating in the City of Madison are 4-8 p.m. Tuesday, Oct. 31.

Children 12 and under can also trick-or-treat at participating retailers at West Towne and East Towne malls from 5-6 p.m. on Halloween. Children must be in costume and accompanied by an adult.

Hilldale shopping center will host an all-ages Trick or Treat from 4-8 p.m., with candy and some special festivities at 21 stores. Look for the “ghost” on the doors of participating merchants on Halloween.