Tomioka is a city situated in the Gunma Prefecture of Japan. As of September 1, 2020, the city covers a total area of 122.85 square kilometers and maintains a population density of approximately 390 persons per square kilometer.
The city is home to the Tomioka Silk Mill, which has been designated as a UNESCO World Heritage Site. The municipality currently serves a population of over 57,000 residents across more than 20,000 households.