The 15th-century palatial headquarters of the Venice Biennale is five minutes from the city’s Piazza San Marco, though the throngs of tourists feel far away. It’s early April and very quiet. You would have no clue that, in just over a month’s time, this will be the hub of operations for the world’s largest exhibition of architecture. It’s in one particularly vast marble room that I find the curator of this year’s biennale, Lesley Lokko, in the middle of a photoshoot.