Middlesex County Mass - all fire stations in black map markers

https://www.google.com/maps/d/edit?mid=13W3fAB7pj36De36XK4qUluAF_jvOnRM&usp=sharing

you can change the base layer map at the bottom of the map index box
on the left of the map

possibly we are using an old version of Google Maps - directions given
for changing map layers are much different on the Internet