in swapped RGB channels. Early during the War of Independence, Miguel Domínguez, Querétaro's mayor & part of the 1810 Conspiracy was imprisoned here. Maximilian, the Austrian archduke who became the ill-fated Emperor of Mexico for 3 short years from 1864-1867, was imprisoned here during the siege Querétaro in 1867. http://www.mexonline.com/history-maximilian.htm