Carcosa is a fictional city in the Ambrose Bierce short story An Inhabitant of Carcosa (1891). In Bierce's story, the ancient and mysterious city is barely described, and is viewed only in hindsight (after its destruction) by a character who once lived there.
Its name may be derived from the medieval city of Carcassonne in southern France, whose Latin name was "Carcaso".
The city was later used more extensively in Robert W. Chambers' book of horror short stories published in 1895 entitled The King in Yellow. Chambers had read Bierce's work and had also borrowed a few other names (including Hali and Hastur) from Bierce's work.
In Chambers' stories, and within the apocryphal play (also titled The King in Yellow) which is mentioned several times within them, the city is a mysterious, ancient, and possibly cursed place. The most precise description of its location given is that it said to be located on the shores of Lake Hali in the Hyades. The descriptions given of it seem to make it clear that it must be located on another planet, or possibly even in another universe.
..."for there be divers sorts of death - some wherein the
body remaineth and
some it vanisheth quite away, with the spirit, this
commonly occurreth only in
solitude (such is gods will) and, none seeing the end, we
say the man is lost,
or gone on a long journey - - which indeed he hath but
sometimes, it hath
happened in sight of many, as abundant, testimony
showeth. In one kind of death
the spirit also dieth, and this it hath been known to do
while yet the body was
in vigor for many years. Sometimes as it veritably
attested it dieth with the
body, but after a season is raised up again in that place
where the body did