Above the vastu-purusha-mandala is a high superstructure called the shikhara in north India, and vimana in south India, that stretches towards the sky. Sometimes, in makeshift temples, the superstructure may be replaced with symbolic bamboo with few leaves at the top. The vertical dimension's cupola or dome is designed as a pyramid, conical or other mountain-like shape, once again using principle of concentric circles and squares (see below). Scholars such as Lewandowski state that this shape is inspired by cosmic mountain of Mount Meru or Himalayan Kailasa, the abode of gods according to its ancient mythology.: