sentences:  Routes.These highways are US 59, which forms the Southwest and Eastex Freeways, and runs southwest-northeast, US 90, which runs concurrently with I-10 from the west county border to I-610, where it becomes the Cosby Freeway, running in a west–east direction, and US 290, which forms the Northwest Freeway, running southeast-northwest.There are currently nine state highways located in Harris County.