I recently spent two days touring the Subak areas.
On the first day I visited the Pura Taman Ayun, a very neat compound which can only be seen from across a hedge. It features 11 roofed pagodas and a canal full of lotus blossoms.
From there I continued to Mount Butukaru and the Jatiluwah rice terraces, a large area of man-made terracing.
Another day I took the steep road that climbes up to the rim of the caldera overlooking the volcanic cone of Mount Batur and its namesake lake. Here I changed into Balinese costume to allow me to visit the Pura Ulun Danu Batur. This large complex is clearly a site of religious significance to the Balinese.
During the descent I stopped at Tegalalang for lunch and to see more rice terraces.
Visiting these sacred sites in Bali is in marked contrast to the usual Balinese tourist haunts of Nusa Dua, Kuta and Ubud.