Near Jaipur on the road to Agra is a small town called Abhaneri which has a giant "step well" called Chand Baori. It was used to collect rain water, but oddly it was also a temple and then a palace!
Click for a zoomed-in version
Here's a view from another angle:
Again, click to see a zoomed-in version.
I love the patterns of light and dark that the steps make based on the angle of the sun!