Through the TA forums, we heard about Klungkung temple (which is also called Kerta Gosa) in Klung Kung. We visited on our way from Ubud to Candi Dasa and it was one of my favorite places. I found the paintings on the ceilings depicting the karmic results of various (mostly bad) actions fascinating. There are many lovely statues throughout the gardens and along the walls. We enjoyed the little museum in the grounds with many old photos with interesting information about the area and its history. The buildings served as court where the local priests would cast judgement over local disputes and the like. The main building sits in the middle of a large pond, or small lake, with lots of lily pads, making it a beautiful scene.
Also, don't be tricked into buying a sarong outside. There are a few pushy sellers near the entrance that wait for cars carrying tourists to pull up to try to make a sale. As soon as you walk through the main gates, you can borrow one from the attendants who will even help you tie it on. If you're in the area, do make the stop.

Be sure to note the beautiful painted ceiling in the small pavilion in the center of the water feature. Remember to wear long pants or a sarong and sash.

This intact royal temple gives you some idea of the power and grandeur of the Balinese kings (the idland was divided into several small kingdoms) before the Dutch conquered it.

Oh to be a king and embody your royal power by building an elegant stone temple that floats in the center of a grand cut-stone garden pool. At great ceremonies, the temple would fill with subjects bowing to the glory at once divine and temporal embodied in the sacred-king seated in regal splendor on the floating temple.

The painted roofs (restored along the lines of badly deteriorated originals ) on the roofs of the temple and judicial pavilions) are particularly notable.

Not a lot of stairs. No pesky vendors inside. Nor to they impose one of the dreadful mandatory guides. (see my other reviews)

Quite old temple but cherished with all its goodness. You will have to wear their traditional cloth wrapped around your waist (Like a Loonogee) and then enter the temple. I personally enjoyed the gamelan and the peaceful silence inside the temple.