The Grote Sint Laurenskerk is the largest and most popular monument of Alkmaar. The church is open and free to visit all summer and on several weekends. Weekly, thousands visit the church amounting to over 70.000 visitors a year. The medieval church is a basilica built in Brabantian gothic style and houses two extraordinary organs: the Van Covelens and the Van Hagerbeer/Schnitger organs, which are still played during various concerts throughout the year.