HMdb.org | Historical Marker Database | June 2019:
Inscription. 
The Gammon House built 1850 a station on the Underground Railroad
Topics. This historical marker is listed in this topic list: Abolition & Underground RR.
Location. 39° 55.03′ N, 83° 48.741′ W. Marker is in Springfield, Ohio, in Clark County. Marker is at the intersection of Piqua Place and West Clark Street, on the left when traveling south on Piqua Place. Touch for map. Marker is at or near this postal address: 620 Piqua Place, Springfield OH 45506, United States of America. Touch for directions.