I've tried googling this and I get everything from the Washington monument to renaissance recreations. I know some were moved to London, Paris, and New York. Aside from Helios and Alexandria, are there any others?
There are several obelisks in Rome. The ancient Romans used special ships to bring them across the Mediterranean to Rome. Two notable obelisks include the ones in St. Peter's Square in the Vatican and the one in Piazza Del Popolo. There is also one in New York City.
There is one in Paris between The Louvre and Arc de Triomphe. Pierre Charles L'Enfant designed that space as well as the National Mall so it's not too surprising.
Istanbul has at least one or two.
They are at the turn points of the old circuis maximus.