Arkham is a fictional city in Massachusetts, part of the Lovecraft Country setting created by H. P. Lovecraft and is featured in many of his stories, as well as those of other Cthulhu Mythos writers.
Arkham House, a publishing company started by two of Lovecraft's correspondents, August Derleth and Donald Wandrei, takes its name from this city as a tribute.
Read more about Arkham: Arkham in Lovecraft's Stories