The columns were made of wood (not stone) and were generally painted red. Mounted on a simple stone base, they were topped with a pillow-like, round capital. Villas A number of compounds known as "villas" have been excavated on Crete, mostly near palaces, especially Knossos. These structures share features of neopalatial palaces: a conspicuous western facade, storage facilities and a three-part Minoan Hall. These features may indicate a similar role or that the structures were artistic imitations, suggesting that their occupants were familiar with palatial culture. The villas were often richly decorated, as evidenced by the frescos of Hagia Triada Villa A. A common characteristic of the Minoan villas was having flat roofs. Their rooms did not have windows to the streets, the light arriving from courtyards, a common feature of larger Mediterranean in much later periods. In the 2nd millennium BC, the villas had one or two floors, and the palaces even three. Art Minoan art is marked by imaginative images and exceptional workmanship. Sinclair Hood described an "essential quality of the finest Minoan art, the ability to create an atmosphere of movement and life although following a set of highly formal conventions". It forms part of the wider grouping of Aegean art, and in later periods came for a time to have a dominant influence over Cycladic art. Wood and textiles have decomposed, so most surviving examples of Minoan art are pottery, intricately-carved Minoan seals, palace frescos which include landscapes (but are often mostly "reconstructed"), small sculptures in various materials, jewellery, and metalwork. The relationship of Minoan art to that of other contemporary cultures and later Ancient Greek art has been much discussed. It clearly dominated Mycenaean art and Cycladic art of the same periods, even after Crete was occupied by the Mycenaeans, but only some aspects of the tradition survived the Greek Dark Ages after the collapse of Mycenaean Greece. Minoan art has a variety of subject-matter, much of it appearing across different media, although only some styles of pottery include figurative scenes. Bull-leaping appears in painting and several types of sculpture, and is thought to have had a religious significance; bull's heads are also a popular subject in terracotta and other sculptural materials. There are no figures that appear to be portraits of individuals, or are clearly royal, and the identities of religious figures is often tentative, with scholars uncertain whether they are deities, clergy or