Maryland Atlas of Historical County Boundaries
John H. Long, Editor; Peggy Tuck Sinko, Associate Editor and Historical Compiler; Douglas Knox, Book Digitizing Director; Emily Kelley, Research Associate; Laura Rico-Beck, GIS Specialist and Digital Compiler; Peter Siczewicz, ArcIMS Interactive Map Designer; Robert Will, Cartographic Assistant
Copyright The Newberry Library 2008
CHARLES (original, extinct)
DURHAM (extinct)
PATUXENT (see CALVERT)
POTOMAC (see ST. MARYS)
PROVIDENCE (see ANNE ARUNDEL)
WORCESTER (original, extinct)