Complex sentence: The church structure is mainly made of red bricks, which is noticeably common among churches in Cagayan Valley, in contrast to other old churches made of limestone and coral stone in other parts of the Philippines.
Split into simpler sentences: The church structure is mainly made of red bricks, which is noticeably common among churches in Cagayan Valley. It is a contrast to old churches made of limestone and coral stone in many parts of the Philippines.