Hybla, built about 1800 by Jonathan and Susanna Mifflin, a Quaker couple, became part of the informal network later called the Underground Railroad. Jonathan Mifflin, a Revolutionary War captain who later became a colonel, and Susanna hid freedom seekers on their estate and helped them escape across the river into Lancaster County, often with the aid of free black boatman Robert Loney. Once across, Susanna Mifflin's brother William Wright, a leading abolitionist in the river region, welcomed them and helped secure their safe passage to other conductors farther east. In 1840, Samuel W. Mifflin inherited Hybla after his father's death, and he and his wife Elizabeth continued these operations until they moved away in 1846 while Samuel worked building bridges for the emerging railroad industry. By the Civil War, Jacob Huber and his family lived in Hybla. During the Gettysburg Campaign, Confederate soldiers marched to Wrightsville to seize the bridge for a crossing into Lancaster County and an advance on Harrisburg, but Pennsylvania state militia and other Union troops, joined by 53 free black men from the river region, briefly resisted before withdrawing across the nearby covered bridge to Columbia. On June 28, 1863, Confederate artillery fired multiple explosive shells at the Union lines from Hybla's yard during the engagement.