Downtown Spooktacula: Grand Junction, Colorado, October 25Halloween comes alive downtown with trick-or-treating, costumes, and street performances. Water Lights at Night: Las Colonias Park, Grand Junction, Colorado, October 11Las Colonias' Butterfly Pond becomes a glowing scene as lanterns drift across the water. Read More: If you're looking for simple fall adventures, you’ll find them in Western Colorado. Quick Ways to Enjoy Fall in Western Colorado Pack your camera, your favorite sweater, and get ready to explore. Here are easy ways to make the most of fall in Western Colorado.