Jules from Lake Saint Louis, MO on 4/11/2011 9:53:31 PM:
Depends entirely on your fitness. Keep in mind that Mother Nature enjoys mixing it up which means you may find yourself riding through driving rain on a water-logged, achingly slow trail. That can add hours to your overall time. I am a fit female rider, mid-40s. I rode Clinton to St. Charles in four days then came back the next year and did it in three. The four-day trip was definitely more enjoyable as there are interesting towns and Lewis & Clark markers scattered all along the trail. Trying to get in 75+ miles AND take in the sites is pretty damn hard. I would recommend four or more days and if you're going through to Machens you'll have to double back the 13 miles to St. Charles as there are no services in Machens.