Adamkó Péter - Dénes György - Leél-Őssy Szabolcs: The Caves of Buda - Our Budapest (Budapest, 1992)
deep Hefty Shaft and peer down to the Radium Chamber. This is the starting point of the 2-3 high, 1-2 m wide and 100 m long corridor which was developed and now takes us to the cave’s new artificial exit. The walls along this interesting trail are decorated in places with dripstone flows and calcite lamellae precipitated on the surface of a thermal water lake once filling the cave. Finally we emerge to the sunshine in the refurbished quarry yard. The cave system of the Castle Hill The Castle Cave extending under the travertine cap of the Castle Hill is one of the most interesting caves of the Buda region both for its genesis and history. Although it was formed within the freshwater spring limestone, the travertine, it is not primarily a system of syngenetic cavities. Somewhere in the vicinity of the present-day Szentháromság Square, an ancient thermal spring deposited a thick blanket of travertine at the level of the Danube bank of that time. Due to the uplift of the Buda Hills and the subsequent incision of the Danube Valley, the spring shifted to a relatively lower level. The ascending thermal waters then reached the surface at the lower layers of the previously deposited travertine or at the boundary of the travertine and the underlying marl. This led to the formation of cavities near the new spring. After centuries of repeated human activities (including broadening and expanding some sections and walling off or modifying others), it is now impossible to determine the original extent of the natural cave and distinguish it from the artificial passages. Neither can we say whether all branches were naturally connected or whether man helped to form this large system by linking arms of separate caverns. Remains of stone tools from one of the oldest known primitive cultures were excavated in the Castle Cave by Ottokár Kadic. They were dated contemporaneous to the finds of the pebble culture of the Vértesszőlős archeological site. The tools were preserved in a depression of the travertine some 3-400,000 years ago. At that time there was no cave yet and the hot water of 19 2*