Directly across from the Catedral da Sé , at the far side of the praça, the magnificently brooding art deco Edifício Sé (Praça da Sé 111, Centro, tel. 11/3321-4400, www.caixacultural.com.br , 9 a.m.–9 p.m. Tues.–Sun., free) dates from the 1930s and serves as the São Paulo  headquarters of Brazil’s federal bank, the Caixa Econômica Federal.
The grandiose, marble-lined main floor and mezzanine have been renovated into a cultural center with interesting temporary exhibits. It’s really worthwhile to check out the bank’s offices and coffers. The wooden office furniture—gorgeously streamlined and made in Brazil —will delight design aficionados.