 There is a popular myth surrounding the former casino which tells of "underground caves" between the Gruta de la Virgen (also known as the Gruta de Nuestra Señora de Lourdes; Grotto of Our Lady of Lourdes) and the building, crossing Agustín Ross Park. During the restoration of the building, in December 2007, it was reported that "two great walls constructed with flagstone, very wide and very close together" were found, but nothing was confirmed afterwards.
