at one time - springfield to Amherst had the largest concentration of detectorists in the country
it had tons of dealers and a bunch of clubs -...
Casper , I can think of similar spots which, for some reason, md'ing caught on in the early days of md'ing: 1960s, 70s, & 80's. And you're right: The *obvious* spots in those areas were pounded to heck. Hence pity the poor newbie who goes there now, and tries to eek out any more oldies from the obvious parks, schools, etc... Even the hard-core experienced guys will be doing good to get more oldies.
Thus the last frontier at such places is private yards, old-town urban demolition, or creative site-research that yester-year hunters might have over-looked.
My part of CA is one such place (a dealer here since the early 1970s, and hunters since even the 1960s). So whenever someone new gets into the hobby, they are picking up the exact same history books that we used 20, 30, and 40 yrs. ago

And they promptly rush out to the defunct resort, picnic sites, adobe sites, parks, etc... that we did. Hence it's gotten so that I mostly travel now to find fresh spots. Some parts of CA didn't have the same pressure. Same might be true for the OP here.