A plaza group directly overlies the principal chamber of the Cueva de El Duende (not to be confused with the similarly named Cueva de Río El Duende), which lies just southwest of the El Duende pyramid. A 2 meter deep midden was discovered in this cave showing heavy use during the Preclassic and Classic periods. A ceramic vessel bearing the earliest dynastic text yet recovered from Dos Pilas was found in this midden. A thick cap of sterile yellow clay covers much of the floor of the main chamber, it appears to have been deliberately deposited in order to cover the entrance to the cave's longest tunnel, which passes underneath the El Duende pyramid and connects with the Cueva de Río El Duende. In the entrance of the cave were found large quantities of rubble, much of it consisting of finely dressed stone that had been stripped from nearby buildings and used to block the cave entrance. James E. Brady believes that the blocking of this sacred cave was a part of a termination ritual carried out by the conquerors of Dos Pilas, who also blocked the entrances of the Cueva de Sangre (Cave of Blood) and possibly the western entrance of the Cueva de Río El Duende, suggesting that the caves were enormously important.