Hadrian's Arch, also known as "Hadrian's Gate", is a huge gate that resembles - in some ways - Roman arches. It was built in honor of the great Roman Emperor Hadrian who was a huge fan of Athens, thanks to its rich cultural heritage. Made of marble, this arch is 18 meters high, and reflects both Roman and Greek culture, having a typical Roman arch design, while the top is reminiscent of Greek gates.