Bucklin's most notable service, however, took place when she was moved to a point lookout at Chesapeake Bay for the winter. Here, she cared for men fighting at the battles of Antietam, Bull Run, and Fredericksburg. In March, Bucklin moved again to Alexandria, Virginia, and then went on to serve at Gettysburg as a field nurse. She recounts in a letter to Mary G. Holland that she was among the first to arrive at Gettysburg and one of the last to leave. Upon her arrival, Bucklin was faced with a line of soldiers awaiting surgery a mile and a half long. At the completion of Gettysburg, Bucklin spent the next seven or eight months nearby at Stoneman's Cavalry Hospital near Washington, D.C. In the winter of 1863, Bucklin came down with a fever. Her illness proved to be quite extensive, and in her aforementioned letter to Holland she writes that the other hospital staff left her for dead. Her illness, however, did not deter her from caring for patients.