The Mexican War of Independence got its start in this region (don't confuse it with the "Revolution" which took place later). This is the corner of the Alhondiga, which was originally a granary. In 1810, an independence movement began, led by a 57-year old priest, Miguel Hidalgo. This was then a Spanish fortress, and Hidalgo's forces took this, spurred on by a miner nicknamed "El Pipila" (more about him later).
Although the rebels took this particular fort, the movement was crushed. Hidalgo was executed, and his and three other leaders' heads were put into the cages hung from spikes (look closely upper right) on each corner of this building. The Spaniards left the heads there for some time.
The War got started on September 15, which is Jennifer's birthday and she was told that makes her an honorary Mexican! It took 11 years before independence, and 600,000 lives. September 28, 1821 was Mexico's Independence Day.