Map Ordering Information

The maps are organized in a rectangular grid that covers the nation, rather than by state or county.

Each map covers 15 minutes of latitude by 15 minutes of longitude, which is roughly 15 miles by 18 miles. (This means they cover exactly four standard 7.5' USGS Topographic maps.) They combine good accuracy with wide coverage, which is why we're so enthusiastic about them!

You can specify the maps you want in one of several ways:

• degrees and minutes of latitude and longitude of the southeast corner of each map.
• the names of the corresponding topographic maps.
• the state and county you want to research.

Contact us at (617) 527-9566. We're happy to help identify the maps you need.

Note that if you specify the latitude and longitude, the values must be on 15 minute boundaries, that is, the number of minutes must be 0, 15, 30, or 45. For example, N40 degrees 37.5 minutes is not a valid value for a map corner's latitude, but N40 degrees 30 minutes is OK.