Log In

Go to Text-Based Medusa

Select base map below to change underlay. This will not affect resources being displayed.

About the Base Maps...

This will create a buffer around a point. Select the buffer size and unit below and click Select Center Point, then click on a point on the map.


Enter latitude (N) and longitude (W) in decimal degrees (e.g., 39.25, -76.73). Be sure to enter a minus sign in the longitude box to indicate W.


Convert from Degrees/Minutes/Seconds

Zoom to (Lat, Long)
Measurement Options
Draw Options
Circle Select
Freehand Select
Buffer Point Select
Clear Selection
Change Basemap


Included in Synthesis Project


URL for the Medusa application has changed!

Please update any shortcuts to


or click the " Research Historic Properties Using Medusa" button on the MHT website's home page

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 includes both architectural resources and 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.

This program provides a map- and text-search based interface for Medusa. Begin by zooming to your area of interest (if you are doing a map search) or open the Text Search tab if you prefer to do a text-based search. Use the Layers tab to select which layers you wish to view. Click on the Base Map Gallery if you wish to change the background map.

IMPORTANT: Note that you will not see any archaeology-related records until you sign in by clicking the Log In link in the upper right. You must have a valid Medusa account to see these records. Users who wish to see "non-archaeological" information do not need an account.

Users who do not need a map interface and prefer the "old" version of Medusa can click on the "Go to Text-Based Medusa" in the upper right.

Get started by zooming to your area of interest!

Other Links (each opens in a new tab)

Available Layers

Select layers that you wish to display below. You may need to zoom in for some layers to be activated.

"Architecture" and "Archaeology" layers contain MHT Medusa database information ("Archaeology" will only appear if you are logged in). "Other MHT Base Data" contains overlays that may be of use for contextualizing this data. Turn these on and off as needed.

Add Other Data

Add a zipped shapefile to the map. Note that the display file will be for reference only; you will still need to use the selection tools to select resources in your project area.

Visit the ArcGis Online Shapefiles help topic for information and limitations.

Text Search

To begin a text search, select the type of search using the buttons below:

A search window will appear with attributes from which you can do your search.

records selected
No records found...

Map Search

Click on a feature on the map, or use the selection tools to select an area. Your results will show up here.

Selection tools are as follows:

Circle Select: Interactively draw a circle, finds all resources that intersect.

Freehand Select: Draw a polygon of any shape, finds all resources that intersect.

Buffer Point Select: Select a buffer size and center point, finds all resources that intersect.

Clear Selection: Clears all existing selections.
records selected.
Click again on the map to select another area.

No records were found at that location. Click again on a feature on the map, or use the selection tools to select an area. Your results will show up here.

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