The Cathedral of the Immaculate Conception has stood in Portland for 150 years. Credit: Roman Catholic Diocese of Portland

Maine’s Roman Catholics are gearing up to celebrate the 150th anniversary of the opening of the Cathedral of the Immaculate Conception in Portland.

The neo-Gothic structure, which is the tallest building in Portland, emerged after the Great Fire of 1866 destroyed the original cathedral that was then under construction.

Bishop Robert P. Deeley will celebrate a special Mass on Sunday.

The event falls on the Feast of the Nativity of the Blessed Virgin Mary. Church officials say that’s fitting since the cathedral’s windows depict the life of Mary, mother of Jesus.

The 10th bishop of the Diocese of Portland, the Most Rev. Joseph Gerry, wrote on the cathedral’s 125th anniversary that the “magnificent” structure is “a noble and uplifting building which turns our hearts and minds to God.”