Location: Casa del Poeta Tragico. The Roman town of Pompeii, including most of its inhabitants, was buried under a several metres thick layer of tephra in the afternoon of 23 November 79 AD, after the plume emitted by a massive eruption of Mount Vesuvius had collapsed. Despite massive destruction, many features - including mosaics, wall paintings and further details - have been preserved in the underground for almost two millennia. The mosaic shown in the photograph means "Beware of the dog!".