What are the Stephen King connections in The Dark Tower series?

Question

There's plenty of connections to King's other works in The Dark Tower. Most notably Salem's Lot.What other connections are there, no matter how big or small?

Answer 1

This isn't the kind of question that can be answered in a couple of paragraphs online--there have been books written on the subject! Just for starters, The Crimson King and the Low Men appear in Insomnia and Desperation, the Turtle appears in IT, Randall Flagg is the villian in The Stand and Eyes of the Dragon, Father Callahan is from Salem's Lot as you've already mentioned.