Known to be the oldest church in Groningen, the Martinikerk was once a modest cruciform-shaped structure dating back to the 13th Century. Dedicated to Saint Martin of Tours, the patron saint, this sandstone church underwent several structural changes, including elaborate extensions in the 15th and 16th centuries, as well as the addition of the iconic Martinitoren, the church's bell tower that was constructed between 1469 and 1482. Underneath its restorative layers, the church still displays numerous elements from its original structure, including 16th and 18th century tombs, as well as evocative frescoes that depict the life of Jesus Christ. The Medieval organ in the church was also reconstructed and enlarged by German organ-builder Arp Schnitger. Today, this grand sandstone structure, a monumental religious landmark from the Middle Ages, dominates the Grote Markt with its timeless beauty.