On July 29, 1773, day of Saint Martha of Bethania, a very powerful earthquake hit the city of Santiago de los Caballeros at around 3:00 p.m. One hour later, an even more devastating tremor that lasted for about a minute hit the city again, in the middle of a strong thunderstorm, destroying churches, government office buildings and private homes.
 It also broke water and food supply chains, as the natives that provided the city fled to the mountains.

On August 2 and 4, captain general Martín de Mayorga presided over the "General Meetings" with the local authorities, including archbishop Pedro Cortés y Larraz, criollo City Hall members, and regular clergy representatives.
They concluded to inform king Carlos III and the Indian Council about the destruction and the eventual move of the city to neighbor "La Ermita" valley, which was not as close to the volcanoes, which were considered the culprit for the destruction of the city at the time.

On December 13, 1773 two strong earthquakes hit the area again,  resting the case of the group that wanted to move to a different location.
Once 1774 the Indian Council pronounced its verdict on the city status and approved the move to "La Ermita" valley.
Matías de Gálvez, between 1779 and 1783, was in charge of coordinating the move.

Possibly the damage caused by the earthquake itself was serious, but not as destructive as the one caused by the city abandonment.
 On January 16, 1775 master builder Bernardo Ramirez start pulling out all reusable construction material from the destroyed buildings to move it to the new capital city, because of a legal order to do so.
 After this, the Palace was left without doors, windows, balconies, ornaments, and so on.
On July 29, 1773, day of Saint Martha of Bethania, a very powerful earthquake hit the city of Santiago de los Caballeros at around 3:00 p.m. One hour later, an even more devastating tremor that lasted for about a minute hit the city again, in the middle of a strong thunderstorm, destroying churches, government office buildings and private homes.  It also broke water and food supply chains, as the natives that provided the city fled to the mountains.
On August 2 and 4, captain general Martín de Mayorga presided over the "General Meetings" with the local authorities, including archbishop Pedro Cortés y Larraz, criollo City Hall members, and regular clergy representatives. They concluded to inform king Carlos III and the Indian Council about the destruction and the eventual move of the city to neighbor "La Ermita" valley, which was not as close to the volcanoes, which were considered the culprit for the destruction of the city at the time.
On December 13, 1773 two strong earthquakes hit the area again,  resting the case of the group that wanted to move to a different location. Once 1774 the Indian Council pronounced its verdict on the city status and approved the move to "La Ermita" valley. Matías de Gálvez, between 1779 and 1783, was in charge of coordinating the move.
Possibly the damage caused by the earthquake itself was serious, but not as destructive as the one caused by the city abandonment.  On January 16, 1775 master builder Bernardo Ramirez start pulling out all reusable construction material from the destroyed buildings to move it to the new capital city, because of a legal order to do so.  After this, the Palace was left without doors, windows, balconies, ornaments, and so on.
Palacio de los Capitanes Generales, Antigua Guatemala