1. Located there is a hypogeum which was discovered in 1973. 2. The Hypogeum as one will not, is a unique worldwide site. 3. The Hypogeum was the Roman-Etruscan tomb of Arnth Veltimna Aules. 4. Substantial quantities of machinery also existed in the " hypogeum ". 5. In 2014, an international team of scientists visited the Hypogeum to study acoustics. 6. Pyramid of Cestius ) and a hypogeum -grotto, overlooking a small pond. 7. The small hypogeum is located nearby. 8. Upon the door of the hypogeum , which still remains, is the following inscription in marble: 9. It is at the Neolithic Hal Saflieni Hypogeum that the earliest known skeuomorphism first occurred in the world. 10. Other megalithic sites in the vicinity include the Hypogeum of & al-Saflieni and the Tarxien Temples.