In addition to the reports that Mike Martin’s treasure had been found in Cambridge, Mass. in 1842; and in Arlington, Mass. in 1884, in 1893 it was reported that a stash was found at Winter Hill in Somerville, Mass.
From the Boston Globe of August 23, 1893:

Sadly, the telling clue in this case is that there were coins dated 1822–the year AFTER Martin was executed.
This was also the second little-known cave rediscovered in urbanized Middlesex County, the first one being the one announced in 1885 near Menotomy Rocks in Arlington in 1885.
Given that tranches of loot were found with the initials “M.M.” nearby in two separate cases, amateur sleuths might try searching for a different criminal with those letters.