U.S. Pavilion: Sarah Sze, Triple Point (Pendulum), 2013. Mixed media.

The Venice Biennale opened to the public on Saturday with national pavilions representing 88 countries—including, for the first time, the Vatican. Massimiliano Gioni, associate director at New York's New Museum, assembled work by more than 150 artists for the biennale's main exhibition.

The show occupies a central place among the pavilions in the city's Giardini and snakes through the Medieval Arsenale in a series of inserted galleries designed by Annabelle Selldorf. The youngest curator to helm the 118-year-old exhibition, Gioni, born in 1973, combined work by similarly young artists with lesser-known pieces by well-established names and relatively unknown outsider artists. His mix of the contemporary and the historic spans more than a century. The exhibition takes its title, The Encyclopedia Palace, from a model by Marino Auriti, an Italian-American visionary who, in the 1950s, designed a babel-like tower to house all of the world's knowledge on a site in Washington, D.C.

Many of the national pavilions are showing work with similarly architectural qualities—if less grandiose ambitions. Click on the slide show above to view a few highlights by Sarah Sze at the U.S. pavilion, Ai Weiwei at the German pavilion, and Jesper Just at the Danish pavilion, among others.