I think, the display didn't achieve its objective. It has poor quality linework. It could have been done much better buy splitting the image into several parts and make the individual images clickable map. Boston and Massachusetts maps Maps showing the Boston area. This map site has several bad maps in the internet.
Most maps are simply scans from hardcopy and put in the internet.
The quality of text and linework are degraded considerably due to loose of resolution. You will see some of the maps that don't work properly on the screen. Massachusetts map of WWW resources. This site also has a link to one of the largest map indexes in the internet. There is a clickable map that is link to another site for more detailed maps or other information.