 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 . 
