Fredericktown is a city in and the county seat of Madison County, Missouri, United States, in the northeastern foothills of the Ozark Mountains. The city is surrounded on three sides (east, west, and south) by the easternmost parcel of the Mark Twain National Forest. A beautiful location to the east of Fredericktown is the Castor River Shut-Ins, where the Castor River travels through large boulders of pink granite. The largest and most accessible recreation area in Madison County is the Silver Mines Recreation Area, which is part of the Mark Twain National Forest. Along with its associated Turkey Creek Picnic Area and Millstream Garden Conservation Area, Silver Mines provides miles of beautiful hiking trails along the sides of one of the deepest valleys of the St. Francis River.