'Kanto' (Japanese: カントー地方 Kantō-chihō) Kanto is a Pokémon region in the Pokémon universe and was the first to be featured in the popular series of games; it was followed by Johto, Hoenn, Sinnoh, Unova and Kalos. It is modelled and named after the Kantō region, a region in Japan, which includes, amongst other cities, the Japanese capital Tokyo and as all the other regions weren't named after somewhere Kanto is the only one that shares its name with a real world location. It was the first region released. The resemblance between the bay formations seen on the in-game map and the actual Sagami Bay, Suruga Bay, and Tokyo Bay formations is particularly striking.
KantoPoke
Kanto Region in the second generationKanto-Full-Map
Kanto Region in the third generationKanto Anime
Kanto Region in the animeKanto
Kanto lies to the east of Johto; they presumably make up a small continent. South of Kanto are the Sevii and Orange Islands. Hoenn, introduced in Pokémon Ruby, Sapphire and Emerald, is supposedly further to the southwest. Routes located wholly within Kanto are numbered 1 to 25; routes 26, 27 and 28 connect Kanto with Johto. Supposedly to the north of this continent is the Sinnoh region. Unova is a considerable distance away and it's unknown where both it and Kalos are in relation to Kanto.