In your opinion, what is one of the most perfect human-made creations?

I am thinking mainly of artistic creations of one kind or another but it could also be a concept or philosophy. The question was sparked by my re-reading of the first stanza of T.S. Eliot’s “Little Gidding” – in my mind an almost flawless creation. I love it for its cadence, its imagery and its meaning. What work is that to you and why, if you care to elaborate?