Vanguard Bank Vanguard Bank is an entirely submerged feature in the southern portion of the South China Sea that hosts three Vietnamese outposts. U.S. Board of Geographic Names: Vanguard BankChina: Wan'an Tan, 万安滩Taiwan: Wan'an Tan, 萬安灘Vietnam: Bãi Tư Chính Occupied by: VietnamLegal Status: SubmergedGPS: 7° 30' 49" N, 109° 39' 58" E Vanguard 1 November 15, 2017 February 23, 2014 Vanguard 2 November 15, 2017 April 26, 2016 Vanguard 3 August 7, 2017 Analysis of Outpost Vietnam Builds Up Its Remote Outposts