US 113 Alternate began at an intersection with US 113 and DE 1 (Bay Road) in Little Heaven. Connections from southbound US 113 Alternate to northbound US 113 and DE 1 and from southbound US 113 and DE 1 to northbound US 113 Alternate were provided by Mulberrie Point Road. The highway headed northwest as two-lane undivided Clapham Road to the town of Magnolia, where the highway followed Main Street. There, US 113 Alternate intersected Walnut Street and passed by the late 18th-century Matthew Lowber House and the Queen Anne–style John B. Lindale House. The highway left Magnolia upon crossing Beaver Gut Ditch and continued northwest as South State Street, crossing Cypress Branch. The route came to the unincorporated village of Rising Sun, where it veered north and intersected DE 10 Alternate (Sorghum Mill Road). DE 10 Alternate joined US 113 Alternate in a concurrency north across Tidbury Creek to DE 10 Alternate's eastern terminus at their junction with DE 10 (Lebanon Road) in Highland Acres.