Kumagai Gumi. 

Operating both within Japan and on an international scale, Kumagai Gumi Co.,Ltd. is a prominent construction enterprise. Its core activities span a vast spectrum of projects, ranging from large-scale civil engineering undertakings such as tunnels, roads, bridges, railways, dams, and airport/seaport development, to diverse architectural endeavors including residential properties, commercial establishments, hotels, government and corporate offices, and facilities for education, culture, healthcare, sports, and industrial applications. The company further extends its expertise to producing asphalt mixtures and performing paving services. Additionally, it provides comprehensive building renovation solutions, encompassing everything from structural assessments and seismic evaluations to design, construction, and post-completion support. Kumagai Gumi also manufactures steel components for shield tunnels and construction machinery, manages steel construction leasing, offers project planning and application assistance, delivers construction-related educational programs, and operates as an insurance agency and technology trading entity for the construction sector. Founded in 1898 and headquartered in Tokyo, Japan, the company boasts over a century of experience in the industry.