I have "heard" of other explorations but not settlements per se. The Canadian
geographers have plotted some of the journeys from the "sagas" down around
Grand Manan Island, NB and Eastport, Maine near Campobello Island where FDR
had his "cottage" (34 rooms) and the St. Croix River Settlement International
Historic Site, ca. 1604 by the French. Another source, a former Suffolk
County, Long Island, NY Historian, claims that a literal interpretation of
one of the later "sagas," places two Irish "slaves" on Long Island,
specifically from Port Jefferson, NY to the nearby "Bald Hills" from which
they could see the Great South Bay and the Atlantic Ocean recorded on one of
the later voyages. These two investigators placed no settlement per se. I
fairly recently read an article in the New Hampshire press by the former
Suffolk County, where he has apparently retired.

Another interesting piece of evidence that, not to date, that I know, has
been shown to have been part of a settlement was the so-called "Spirit Lake"
runestone, found in Maine, next to a lake of that name. An interesting
restudy of it was done by a cryptographer of World War II fame, (I believe he
cracked or helped crack the "Mayfair" code. the Imperial Japanese Navy code)
who claimed, that possibly from his description of the scripts one might
suppose that at later and later dates Norse runes were kept in code by and
from the stone, for "bishops," as they had been Christianized. Although it
looked "phony," the Spirit Lake runestone could be decrypted according to
him, though not enough information was present on this one stone to do so. It
has been my offhanded experience to know of an archaeologist who was hired
with crew to do some limited test excavations in the vicinity of this lake
(or another) that to my knowledge produced no artifacts of occupation of that
time period.

As to the Vikings in Greenland, I am of the persuasion that a number of
factors came to be, including the change in climate, possibly symbolic of a
friendship that also went cold with the proselytizing that may have
accompanied the new order in Iceland, if the "code-breaker's" hypothesis is
correct. Maybe they were arguing over a meteorite, a known source for Inuit
knives in some contexts.

George Myers