From the outside, the French-styled Correo Central (Central Post Office) is a frothy white wedding cake of a building, while inside its all tiered galleries topped by a beautiful glass dome. Built in 1882 on the northwest corner of Santiago's Plaza de Armas, the Central Post Office, designed by Chilean architect Ricardo Brown, has been a national monument since 1976.
Next door to the Palacio de la Real Audiencia de Santiago, aside from buying your stamps, the Correo Central is also home to the Museo Postal y Telegrafico. Dedicated to Chile's postal history, here you can see a huge collection of stamps from around the world.
On Plaza de Armas 559, Correo Central is open from 8:30am-7pm Monday to Friday, and from 8:30am-1pm on Saturdays. The nearest metro is Plaza de Armas. The post office museum is just off to the right side of the Correo, and you can walk right in — entrance is free.