Ranakpur Jain Temple
I was quite taken in by this temple. It's a Jain temple, a religion that I think isn't that well known outside of India. I only heard about it within the last few years, and don't know that much about it overall, besides it's emphasis on non-violence. Mahatma Gandhi was influenced by Jainism during his youth, and his application of the Jain principle 'Ahimsa' of non-violence was prevalent in the development of his own Satyagraha (truth force) principle.
I probably spent a solid 1.5 hours walking around the temple. It's about 40,000 sq. ft., or to put that in perspective, a pretty decently sized Best Buy. Instead of admiring electronics I was admiring the amazing details found everywhere you look. It's truly an amazing temple and well worth going a couple hours out of your way from Udaipur to see it. I'm so glad I did.