Throughout the centuries, the San Guillermo Parish Church has accumulated treasures that serve as proof and reminder of the devout faith of Dalaguetnons and their high reverence for religious symbols and images.

These are now housed at a space in the old rectory that has been converted into the San Guillermo Parish museum.

Many of the religious artifacts and relics date back to the 1800s and include a chandelier, carousel, and ciborium in silver; long carved benches made from the hardwood of the Magkono tree and vestment cabinets that are over three centuries old; confession box from the same period; and wooden ceremonial chairs.

The museum was put up during the stint of Msgr. Phil James Tumulak, just a year before Dalaguete celebrated in 2011 the 300th anniversary of the founding of the parish.

An old canvas painting of the Last Supper, Ecce Homo image, a missal with lock from the early 1900s, musical instruments, and earthenware jars are other museum treasures.

A cabinet keeps the old records of the parish containing details of baptism, confirmation, marriages, and deaths from as far back as the early 1800s.