Around the dome of the Old Parish Church there is a secret passage in U-Form. Secret passages built in the thick walls of the southern transept afforded a hidden look-out for sentries who watched for the landings of the pirates in the non-distant bays and then relayed news of the pending invasion to the locals and warned the garrison of Mdina in the north by means of smoke signals from the roof of the church. The secret passage was discovered in the 1960s where found considerable amount of human bones.

The story beliefs these were buried alive with these passages during the last siege of 1614. One can still notice these bones in the secret passages.