Undermining

Rochester shows that taking a castle could require several methods working together: bombardment, undermining and cutting off supplies. John won the siege, but he did not then capture London. A local military victory had not ended the rebellion.

The crusaders constructed wooden siege machines and towers to attack the defences. They also tried undermining: digging beneath a tower, supporting it temporarily with timber, then burning the supports so that it would collapse. Bowmen and crossbowmen protected the men doing this dangerous work.