city, northwestern Chiba ken (prefecture), east-central Honshu, Japan. Lying on a flat plain along Tokyo Bay, it is separated from the city of Tokyo to the west by the Edo River. Urayasu was a thriving fishing village during the Edo (Tokugawa) period (1603–1867) but grew only slowly until coastal land-reclamation projects in the 1960s expanded its area fourfold. In 1969 a subway line was built connecting the town with Tokyo, and its population grew rapidly thereafter. The completion of a rail line (1988) between Tokyo and Urayasu further stimulated the city's commercial and industrial development. The city is also served by the Wangan Expressway, part of a highway system encircling the bay.

In 1983 Urayasu became the site of Tokyo Disneyland, a theme park duplicating the original Disneyland in Anaheim, Calif. Tokyo DisneySea, with several ocean-themed “ports,” opened next to the park in 2001. One of the most popular recreational attractions in Japan, the park spurred the growth of nearby hotels and other accommodations, including several Disney-run resorts. Pop. (2005 prelim.) 155,287.