Evergreen Mountain Loop is a short drive from Denver and is perfect for a quick getaway. Evergreen Mountain boasts everything from being dog-friendly to trail running to hiking to mountain biking.
The way up Evergreen Mountain is actually a few different trails stitched together throughout Alderfer/Three Sisters Park. The trail connects to both parking lots in the park, so if one is full you can just start from the other one, giving you lots of options for a quick day-hike.
If you start from the first parking lot, the trail is across the road - Evergreen Mountain Trail East. This portion takes you up the majority of the mountain via a series of switchbacks and long, flat stretches. It eventually connects with Summit Trail, a partial loop that does what it says - takes you to the summit. From here you can see incredible views of the Front Range and grab a seat on a rock to eat some snacks! There's a scenic overlook spur off this trail, too, that's worth the extra 0.2 miles.
After you reach the top, you can choose to go back down the way you came or make the hike into a loop. I recommend the loop, because it gives you a chance to really explore the western half of the park. For this, you'll take Evergreen Mountain Trail West downhill and pass some information about the Lodgepole Forest Management Project. Eventually you'll connect with Wild Iris Loop. If you're at the first parking lot, you'll only take this for a few dozen feet before connecting with the Ranch View Trail (if you're at the second parking lot, this loop takes you back to your car). Ranch View Trail takes you back to Evergreen Mountain Trail East and from there back to the parking lot.
The trail is well used and often popular on the weekends, but as it winds its way up the mountain it is easy to have time to yourself. Always be aware of bikers, though, and make sure they have room to get around you.