Visit an important piece of the region's history on your next Downstate Illinois adventure. In an area once known as Calvert Hallow, Army engineers built the Stone Arch Bridge over a century ago as part of the National Road. Each stone was shaped by hand and no mortar or concrete was used. The stones were clamped together with keys to prevent slipping. See for yourself the impeccable craftsmanship that has allowed the bridge to remain for over 100 years. Book your adventure in Marshall, IL today!