The Boskapel is a field chapel on the Lichtenboslaan in Olmen.
According to legend, there was already a chapel on this site in the 8th century, during the time of Willibrordus. In the 11th-12th century a new church was built, located more to the north, on the site of the current St. Willibrordus Church. We know with certainty that a chapel stood here in the 16th century, which was referred to as Capella in Campo (heath chapel). It was dedicated to Saint Willibrord and Our Lady. Pilgrimages were organized to this chapel in the 17th and 18th centuries. They sought relief against various ailments, such as fever, leg diseases and ulcers. After the 18th century, the chapel fell into disrepair.
In 1841 the old chapel was demolished and the current, smaller, chapel built. This one is a few meters away from its predecessor. It is a brick building, covered by a gable roof on which there is a ridge turret. The choir is round. The altar is made from part of the tombstone of Laurentius Janssens, who was a benefactor of the chapel. The remainder of the tombstone is located at the rear of the chapel.