Kanto is a Pokémon region. It is very, very well known for being the first Pokémon region. It is home to the first 150 Pokémon (plus Mew) as well as many well-known cities, landmarks and people, such as the Gym Leaders.
This is the very first place that many veteran Pokémon players and fans have ever played in, and it serves as a nostalgic place for those who were kids when Pokémon first released in America.
Recessional of the Red Dragons[]
Mary, the oldest out of all her cousins, was a Pokémon Trainer born and raised here, specifically in Pallet Town as she became its own Champion!
She was Trudy's closest friend from Earth, and on one night she called her via tablet inside the Bebop, finding out about her mourning over Spike. She persuaded Trudy to tell Jet and Faye on the vision she had and that she was welcome to visit her if the Bebop should drop her off.
Trudy, Jet, Faye, X and Zero stopped by at the Saffron City airport, and Mary met up with them as she escorted them thru Viridian Forest to her home in Pallet. They heard about the upcoming Red Dragons War and her Pokémon comrades caught up. As did her cousins with their cohorts. Moments later the special forces left for Abel City for equipment and supplies.
The ReBoot Multiuniverse[]
Akari has visited the Kanto region catching more wild Pokémon. It was also mentioned that she discovered a defective computer in the destroyed lab of New Island before she was brought into Mainframe. She went there again as she met up with a wounded Porygon escaping from Trojan Megabyte, and Mewtwo suggested her to train it as she travels thru Hoenn, Sinnoh, Unova and Kalos.
Ikran's Lost OoT/Pokemon crossover[]
After Zelda II completed her journey in Johto, she arrived in the Kanto frontier where she saved and was raised by the Mew duo. She was actually taken from the Kanto frontier to Hyrule, along with all her Pokémon. They'd been separated into different regions, and it soon turned out it was Rauru who saved them from a dark stalker she knew.