The Sint-Lievensmonstertoren, also known as the Dikke Toren is a 62 metre tall, unfinished, free standing church tower in Zierikzee, Netherlands. The accompanying church was destroyed by a fire in 1832.
In 1454 work started on a church tower, designed by Andries I Keldermans in the Brabantine Gothic style. It was planned to be, according to different sources, either 130 metres or 204 metres tall. The work was continued by his relatives Antoon I Keldermans and Rombout II Keldermans. Work on the tower halted in 1530, when the city went through a financial crisis. The tower is now 62 metres tall, on a base of 24.5 metres by 24.5 metres. Since 1881, it is a property of the state, and it has been designated a Rijksmonument. The name doesn't refer to monsters, but to a minster.