The square ( also called by its former name Terreiro do Paao ) , wholly wiped out by the great earthquake of 1755 , has seen its share of watershed political King Carlos and his son were felled by an assassin 's bullets there in 1908 , and it was the site of one of the first uprisings of the Carnation Revolution of 1974 .
There was an earthquake in the mid 18th century that destroyed a square .