Another venue we toured and loved (but unfortunately requiring an SUV and a bumpy ride on a dirt road), Piney River Ranch is located just outside downtown Vail and offers gorgeous lake views and hiking trails. Be warned--you definitely need an SUV for this one, and it's a slow drive (but definitely worth it). Excellent choice if you're looking for light hiking or just an opportunity to check out the mountains; you can see everything from the trailhead.
Located close to Breckenridge and on the way to Vail, this trail features a 8 mile hike to and from Quandary Peak, one of the local 14ers. This trail is particularly frequented by mountain goats! Please do not attempt if you are not accustomed to high altitude.
If you're from Colorado and accustomed to the altitude, this is one hike that Bethany strongly recommends! Located close to Vail, the 10 mile loop covers 4 different 14ers. If you are not accustomed to high altitude, however, please do not attempt this.