Although there are no hospitals in Watertown, there is a Doctor's Express Urgent Care center open 7 days a week and a 24 hour CVS. Mount Auburn Hospital in Cambridge, MA is the closest Emergency Facility. Watertown is just a few miles from all the major hospitals in Boston.
Hospital locations:
-24 Hour CVS: 27 Main St. Watertown, MA
-Mount Auburn Hospital: 330 Mt Auburn St. Cambridge, MA
-Boston area hospitals: http://www.house.gov/capuano/links/ma_hospitals.shtml
-Docters Express: 376 Arsenal St. Watertown, MA