Baltimore County

I have plotted virtually all of the original land grants for Baltimore County. Since its founding in 1659 (a date that is assumed, but has never been proved) there have been over 5400 patents as well as thousands of surveys for leases and for land that, for some reason or another, was never patented. Since its founding, there have been a number of changes in the County's borders:

  • Cecil County was originally considered to be a part of Baltimore County, but was designated as its own County in 1674
  • Harford County was split off in 1773
  • Carroll County was formed in 1837 from a part of Baltimore County (and Frederick County)
  • In 1851, the City was split off as a separate entity
  • On multiple occasions, the last in 1918, portions were taken into the city
  • As late as the 20th century, the boundary between Baltimore and Carroll Counties was moved to the east when, during a drought, the original mark on a submerged railroad bridge became visible, and caused a new survey to be done.
  • There have been several adjustments of the border between Baltimore and Anne Arundal County

From the beginning, I have used DeedMapper from Direct Line Software to plot all these patents and various other deeds and surveys. The following files may be downloaded to be used with DeedMapper. I suggest that you first create a new folder on your computer. Download the following three files into the new folder by right-clicking on each one in turn and choosing Save Link or Download. Once that's done the zip file needs to be extracted into the same folder.

If you have any questions, please e-mail them to