Houston Astrodome - world's first multi-purpose domed sports stadium

When it opened in 1965, the Houston Astrodome was the world's first multi-purpose, domed sports stadium and was widely touted as an engineering landmark at the time. It housed the Houston Astros (MLB) and Houston Oilers (AFL/NFL) and introduced innovations including a fully enclosed playing field and domed seating bowl. The structure was popularly nicknamed the 'Eighth Wonder of the World' by contemporaries; that nickname is a historical contemporary claim rather than a formal designation.