Patrick Hallihan, Superintendent of Arlington National Cemetery, holds up a map as an example of what had been used by the cemetery

Arlington National Cemetery on Monday made available to the public a massive electronic database detailing the gravesites of the approximately 400,000 people buried there.

The cemetery debuted an interactive map available through its website and through a free smartphone app. It uses geospatial technology to hone in on specific graves and can also be searched by name.

It can be accessed through the cemetery’s website arlingtoncemetery.mil/Map/ANCExplorer.aspx.

When a name is called up, a viewer can see when the person was buried and the dates of their birth and death. Photos of the front and back of the headstone can also be viewed. Monuments and memorials that commemorate the service of specific military units are also included in the database.

The application also highlights some of the notable graves throughout the cemetery that are popular with the roughly 4 million visitors annually that the cemetery draws.