Jason Bay was a body of water on the coast of one of the planet Manticore's continents.

The name was somewhat misleading, as it was more like an inland sea hundreds of kilometers long. The bay was located near Manticore's equator, near the capital city of Landing, and was named for the colony ship Jason. Saganami Island, the location of the Royal Manticoran Naval Academy, was located near Jason Bay, and the Royal Marines' advanced training facility was at the tip of a peninsula, also on the bay. (HH1)

Stephen DuMorne enjoyed the weather so much that he moved his entire family to the region. (HH2)

Honor Harrington's Bay House, given to her by the Queen, was located on Jason Bay across from Landing. (HH10)

Triton Island, the royal family's retreat, was located sixty kilometers from Landing in Jason Bay. (MA3)