Click on the .zip links to save locally. Once downloaded, unzip/extract the .dtm file.
Refer to the Orthophoto Index pdf format of ix_oq.pdf
file size 4MB to determine which files(s) to download.

View Datalayer Description page
The coordinates in the following files are referenced to the Massachusetts State Plane Island Meters pdf format of Ortho Island Index
coordinate system:

Last Updated 7/11/2011