We're talking about the Royal Hospital of All Saints, the first central public hospital building established in Portugal. Its foundation stone was laid in 1492 as part of a reform led by King D. João II, but its completion would only come during the reign of King D. Manuel, even though the hospital started operating before that.
The hospital left its mark on the city, and within its walls, you could find a pharmacy, a kitchen, a pantry, a laundry, administrative offices, and facilities for staff. During the reign of King D. João III, a house for the mentally ill and a ward for convalescents were added. However, two fires would threaten the building: one in 1601 and another in 1750. On November 1, 1755, the great earthquake would completely devastate the hospital - the Hospital of All Saints was thus destroyed on All Saints' Day.
Meanwhile, temporary hospitals were established in São Bento, in the Almadas' house, in Rossio, and at the Gates of Santo Antão so that, twenty years later, the Hospital of All Saints would relocate to the College of Santo Antão, where it would be renamed the Royal Hospital of São José in honor of the king. The hospital still stands today on José António Serrano Street.