30 architectural masterpieces everyone should see in their lifetime

Buildings may be some of the most impressive works of art we have.

After sinking untold sums of money into their construction, we can walk through the finished products and even live inside them.

Business Insider has selected 30 buildings that push the boundaries of structural expression. We think you'll love them.

Drake Baer contributed to an earlier version of this article.

The oldest building we know of is Göbekli Tepe in present-day Turkey. Built somewhere around 9500 BC, archaeologists aren't certain of its function, but it was probably religious.

Since then, humans have built some pretty rad structures. In the past year, we've seen futuristic openings like the Fulton Center in New York ...

... and the Penleigh and Essendon Grammar School in Melbourne, Australia.