How to Request GIS Data

The Maryland Historical Trust (MHT) maintains geographic information system (GIS) data on Maryland’s historic, archaeological, and cultural resources. These datasets support preservation planning, research, documentation, and public information. 

You can view data online for free through Medusa or download the data through Maryland Integrated Map (MD iMap) GIS portal on your own computer or at the MHT Library. If you need specific GIS data for research or planning purposes, you can request those layers directly from MHT. 

What’s available online 

MHT maintains several GIS layers for cultural resources, including: 

• Maryland Inventory of Historic Properties (Architecture)
• National Register of Historic Places boundaries
• Historic preservation easements held by MHT
• Heritage areas certified by the Maryland Heritage Areas Authority  

Archaeological data are restricted to qualified users (professional archaeologists) because of the sensitive nature of site locations. All others are available for public use. 

How to request archaeological or custom GIS data 

1. Download and complete the GIS Data Request Form: Use the GIS Order Form and License Agreement - PDF - 916.22 KB to specify which datasets you need.
2. Review and agree to the data license: The license describes permitted uses and attribution requirements for MHT datasets. Please note that while much of the data is available online, there is a fee associated with MHT processing data requests.
3. Submit your request to MHT: Email the completed form to the Historic Preservation Information System Specialist. MHT provides the requested layers as shapefiles. If the files are large, they may be sent on physical media (CD or DVD). 

Access to archaeological data is limited to users who meet the Secretary of the Interior’s Professional Qualification Standards for Archaeology. If you qualify, you can request a Medusa account for archaeologists. You will need this account to access the data.