These days (and probably forever going forward) altimeter watches either use GPS or barometric pressure to figure out your altitude.

The Suunto Vector has long been the solid, reliable watch in the Suunto altimeter watch line. While the Vector has a great reputation, it is ten years old and Suunto was looking to replace it with a new generation of watch. The Suunto Core came out in 2007 as the "next" big thing in the Suunto watch family. The Suunto Core promised a full feature set, including an altimeter, barometer, storm warning function, and compass.