The Monument to the Martyrs was built in 1841 as a Gothic spire building in memory of the three bishops, Clemmo, Latimo and Ridley, who were hanged and burned alive during the reign of Queen Mary from 1555 to 1556. Next to it is Oxford's oldest building, the Saxon Tower of Oxford, built in 1040. The tour guide suggested that the monument was also one of Oxford's landmarks. Take photos quickly, but he didn't know where the older Saxon Tower next to it was. It's probably the last one.