The Basílica del Santisimo Sacramento is located in the Retiro area, just behind the Kavanagh Building, at San Martin street 1039. Construction was ordered by one of Buenos Aires´ high society ladies form the beginning of the 20th Century: Mercedes Castellanos de Anchorena. She was heard saying that if she lived in a palace (the Palacio San Martín, current venue of the protocol section of the Foreign Services Department) so should her God have his own palace. The church was finished in 1916, and became one of the most luxurios ones in the city, elected by a lot of celebrities as the church were they married.
The body of Mercedes Castellanos de Anchorena rests in the underground vault of the church. The original idea was to use the cript as the resting place for all of the Anchorena family, but in the end she is the only memeber that rests there. The rest of the family can be found in their own mausoleum in the Recoleta Cemetery.