The race is run on the popular Chubb trail.  The 25k will do one out & back & the 50k will do two. The trail itself varies from  a gravel service road, to a mostly dirt trail along the Meramec river, to a mile-long series of climbs, to  finally a rolling trail that winds through the hills of the Meramec River.  There are no stream crossings.  If the Meramec River is well above flood stage then the race will be rerouted.  There are two railroad crossings and extreme caution must be taken because the trains come through this area at a high rate of speed.  Runners may see deer, turkey and other wildlife throughout this trail run.