Graphic designer and self-professed transit nerd Peter Dovak has created an interesting and rather extensive project that sees him take some of the world's subway systems, and illustrate them into simple, minimal designs.
You can purchase some of Peter's designs on his Society6 store - definitely worth a look, even if you're not willing to buy, they're so interesting to look at. For more of his work, check out Peter's Behance page.
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