I don't think you can classify it as an "official" adventure if everything goes as planned. I've never had a plan called to perfection and that includes today's adventure.
Tim Hola and I have been talking about this one for a while and today we tried it: Leave Tim's house on Mtn. bikes and ride 15 myles to the start of the Colorado Trail, ditch the bikes/gear and run 21 myles to the Platte River and back. Didn't happen that way. More like: Leave Tim's house in the pre-dawn hours, try an unknown path to the trail and the rest is pretty much down hill.....
About a mile into the ride Tim says, "I've always had bad luck with flats going this way." Sure enough about 1/2 hour later his front tire was flat and mine was riddled with thorns. I tried pulling 3 or 4 out with a hisssssing sound so I left them in. I didn't have a pump or spare tube, Tim did but the spare went flat about an hour into the ride. We turned around and ditched the bikes/gear along the lower portion of the Platte River and did a modified loop back to his house. And just to add to the adventure we ran through the Platte River on the way back to remind us of the ol' Coach Weber races out there.
So at the end of the day we improvised and got a better than expected workout in. One hour on the bike (~10 myles) and then a 2 hour run (~17 myles) back to his house. Lesson here is be adventurous with new things (or paths) but listen to your instinct - I should have listened Tim. We're gonna try it again next weekend - I hope it's as good of weather as it was today!
Below is the elevation and pace of our run