Karuizawa is situated on the border of Nagano Prefecture and Gunma Prefecture. Nagano Prefecture belongs to the Chubu (central) region of mainland Japan, boasting incredible wilderness, surrounded by mountains called the Japanese Alps.

This website separates Karuizawa into five different areas:
Oiwake Nakakaruizawa Shinkaruizawa,Kyukaruizawa Minamikaruizawa Shiozawa,Hotchi
Each area has its own unique characteristics and attractions.