Hadera (hədāˈrä) [key], town (1993 pop. 50,700), W Israel, on the plain of Sharon, near the Mediterranean Sea. Manufactures include tires, paper, and processed foods. The town has a large electric power plant. Hadera was founded in 1891 by Jewish settlers, who drained vast malarial swamps and planted groves of citrus fruit and fields of grain. The ruins of Caesarea Palestinae are nearby.