The ‘Gambrill Mill’ wayside marker is beside the parking lot for the mill, whose entrance is on Urbana Pike (Maryland Route 355) about 0.9 mile south of the current National Park Visitor Center. (39.367413° N, 77.387372° W; map)
The mill provided shelter for its owner and Union wounded during the Battle of Monocacy. It survived the postwar yeras and was acquired by the National Park Service. The mill building served as the Visitor Center for the National Battlefield Park until 2007.
The mill area is a trailhead for a half mile walking trail that loops down to the Monocacy River, overlooking the railroad and turnpike bridge sites that were the scene of heavy fighting during the battle. The Burning of the Bridge and Fleeing for Their Lives wayside markers are on this trail.
From the marker:
Mill owner James H. Gambrill used his wits to survive the turmoil. A Southern sympathizer, he sold flour to Northern troops as they set up their line of defense on his land. During the battle he took refuge inside the mill with Samuel S. Thomas and two friends who had escaped their four-day impressment in the Union army. The Federals turned the mill into a makeshift field hospital even though it was under near-constant fire. When the fighting ended, the four men emerged from their hiding place under the waterwheel. Gambrill and his mill had survived the Battle of Monocacy.
The neat, well-appointed mill was up-to-the-minute, and its output was greatly appreciated in the homes of a considerable radius. It was pleasure to accompany the big wagon team…to Gambrill’s.”