Saigon River Tunnel is an underwater tunnel that opened on November 20, 2011. It runs underneath the Saigon River in Ho Chi Minh City, the largest city of Vietnam. The tunnel was built with capital from JICA’s ODA, in conjunction with a consortium of Japanese contractors. The tunnel connects the existing urban center of Ho Chi Minh City with Thu Thiem New Urban Area in District 2. The Saigon River Tunnel is part of the East-West Highway, an important road project under construction to ease the congestion of transport in the inner city as well as transportation from downtown to the Mekong Deltaregion. The existing downtown was previously only linked with the Thu Thiem New Urban Area by many bridges, namely: Thủ Thiêm Bridge, Phú Mỹ Bridge and Ba Son Bridge.