Medusa, Maryland's Cultural Resource Information System

About Medusa

Welcome to Medusa, the Maryland Historical Trust’s online database of architectural and archaeological sites and standing structures. The Maryland Historical Trust, home of the State Historic Preservation Office (SHPO), is the official repository for the Maryland Inventory of Historic Properties (MIHP), which as of early 2015 includes some 40,000 architectural resources and 13,000 archaeological sites. The database includes records for the National Register of Historic Places (NRHP) properties in Maryland, determinations of eligibility (DOE) records, and records for properties in the Maryland Historic Preservation Easement program.

Access to paper records is free and open to the public by appointment at the MHT Library in Crownsville, MD (access to archaeological data is restricted to qualified individuals). Medusa provides an online access point for users, both at the MHT Library and off-site. The database can be searched in a variety of ways, both map- and text-based.

Web access to all of the architectural data is open to the public. Access to archaeological site locations and detailed site information is restricted and password protected and will be granted to qualified individuals on a need to know basis. Click on the Register for an Account link to submit your qualifications and to receive an account.

Medusa is an evolving system, and both maps and database records are updated and added constantly. Users are encouraged to notify us about additions or corrections that may be needed by clicking the Submit Feedback link. Please include references or other documentation for changes or additions. New sites will be added when received.

A major upgrade to Medusa, incorporating a map-based searchable interface, is planned for late 2015. Check back for details!!

Frequently Asked Questions

What does "Medusa" mean?

The name is not an acronym; it’s merely a code name used for years for Maryland’s in-house state architectural and archaeological database.

What is included?

Medusa includes: (1) the Maryland Inventory of Historic Properties; (2) the state archaeological survey; (3) National Register properties in Maryland; (4) determination of eligibility (DOE) records; and (5) properties in the Maryland Historic Preservation Easement program.

What do the colors mean?

The different background colors on the forms and search results pages (red for MIHP, blue for archaeology, purple for National Register, green for DOE, and yellow for Easements) correspond to the colors of the resources in the state's GIS database. These colors are intended to make it easier to navigate the individual form types in the system.

How do I see these resources on a map?

Unfortunately, at present the GIS map database can only be viewed at the MHT Library in Crownsville, MD. As noted, we are working on a major upgrade that will provide interactive maps along with the Medusa database remotely as well as in the MHT Library.

Do I need to log in? Why?

You only need to log in to view archaeological site information, as access to that information (especially site location) is restricted and granted to qualified individuals on a need to know basis. You can request an account by clicking Log In in the upper right of the screen, and then choosing Request New Account.

How do I visit the Library?

The Maryland Historical Trust Library is open to historic preservation consultants on Tuesdays, Wednesdays, and Thursdays by appointment only. For further information or to schedule an appointment, contact Lara Westwood by email at or by phone at 410-697-9546. Details about visiting the Library are also available at the MHT Visting the Maryland Historical Trust Library as a Historic Preservation Consultant" page.

As noted above, all material relating to Maryland's archaeological sites is accessible only to qualified researchers with a valid Medusa account. If you need access to this material, and you do not already have a valid Medusa account, please be sure to allow sufficient time for your account request to be processed.