La primera mención escrita de Sestao Historical milestone · Sestao, Bilbo Handia / Gran Bilbao, Bizkaia Image of Sestao, not of the place itself. The oldest documentary reference to Sestao appears in 1322, in the fuero (charter) of Portugalete, where the place is cited as 'Santa María de Sesto'. 1322 Photo: Rampelas (CC BY-SA 4.0) What to see and do in Sestao