The Sendai-jo Castle was a mountain castle with a defense system utilizing the natural topography of the mountain, while the construction of the castle town at the foot of the Sendai-jo Castle became a full-scale construction mobilizing 1 million people in total for the comprehensive development throughout the area.
仙台城は山城で天然の地形を利用した防御であるものの、仙台城下の城下町は全面的な開発であるため、のべ百万人を動員した大工事となった。