Construction began on La Plata's spectacular neo-Gothic cathedral in 1885, but the church wasn't inaugurated until 1932, and tower construction was only completed in 1999. The cathedral was inspired by medieval predecessors in Cologne and Amiens, and has fine stained-glass windows and polished granite floors; 90-minute tours (11am, 2:30pm and 4pm Monday to Friday, reservations necessary) include the museum and an elevator ride to the top. There’s also a gift shop and cafe on-site.