A native of Germany, Gustav Gollbach was ordained a priest in the Oblates of Mary Immaculate Order on April 21, 1906. He immigrated to Texas soon after his ordination, and served churches in Del Rio, Castroville, Mercedes, San Benito, and Ballinger before coming to Rio Grande City in 1924. Serving as pastor of Immaculate Conception Church until 1937, he built a replica of the Grotto Shrine at Lourdes, France, using petrified wood and native stone from the Roma area. Dedicated in 1928, it has become an important historic site in the Rio Grande Valley.