The Facultad de Matematicas is located on San Joaquin Campus, one of the four campuses of the Pontificia Universidad Catolica. The address of the campus is Av. Vicuña Mackenna 4860, San Joaquin, Santiago. The campus is just in front of the Metro station San Joaquin on Line 5. During the morning from 6 to 9 am and the evening from 6 to 9 pm, Line 5 of the Metro operates 2 services and the trains don’t stop at each station. Only the red train stops at San Joaquin station - look out for the red lights on the train carriage before you get on the train.
It is safer to cross the footbridge to get to the campus rather than crossing the road. You will find a global map of San Joaquin Campus here. On this map the way to the Facultad de Matematicas from the Metro is printed in red.