Yokosuka Naval District (横須賀鎮守府, Yokosuka chinjufu) was the first of four main administrative districts of the pre-war Imperial Japanese Navy. Its territory included Tokyo Bay and the Pacific coasts of central and northern Honshū from the Kii Peninsula to Shimokita Peninsula. Its headquarters, along with most of its installations, including the Yokosuka Naval Arsenal, were located in the city of Yokosuka, which constituted the Yokosuka Naval Base.