The Heiankyo was an older Japanese city, today known as Kyoto. Its design is interesting in particular, following the Chinese rules of Feng shui — divided into four sections with various temples, an even split in the middle, with a larger, proper building called Dairi.
Looking at the simplistic layout in the browser game Heiankyo Parameters, it all becomes clearer, and without it feeling like a history lesson. The goal is to establish the Heiankyo while fending off aliens, represented by yellow fields. Meanwhile, players have to fill in all the empty land with housing, building up temples, markets, and upgrading their army.