The Dickeyville Grotto is located in Dickeyville, WI. Inspired by Father Dobberstein's Grotto of the Redemption, Father Matthias Wernerus built a Crucifixion Group in a corner of cemetery of the Holy Ghost Catholic Church Parish in 1920. In 1925, he built the Eucharist Altar. From 1925-1929, he worked on a much bigger project: the Holy Ghost Grotto (also known as the Grotto of the Blessed Virgin).
The Holy Ghost Grotto is 25 feet tall, 30 feet wide, and 25 feet deep. Thousands of colored stones, molten glass, gems and jewels are embedded in cement. On each side of entrance is a pillar bearing a flag – one for religion, one for patriotism. The altar inside has statues of angels, the Virgin Mary and Child.
The Grotto was actually a community project. Concrete was poured into slabs or modeled around metal forms and then studded with bits of glass, tiles, crockery, stone, shells, costume jewelry and other materials donated by parishoners.
In 1929, Father Wernerus began another shrine entitled "Patriotism in Stone", a tribute to Columbus, Washington and Lincoln. While gathering materials for another work, Wernerus caught pneumonia and died in 1931.
For more, see these websites: 1, 2, 3, 4, 5, and 6.