Tamagawa is a river located in Tokyo, Japan. It flows approximately 138 kilometers and is known for its scenic beauty and recreational areas. The river is an important water source and supports various ecosystems along its banks. The river is also famous for its historical significance, as it has been a vital waterway for transportation and trade. Additionally, the Tamagawa Aqueduct was constructed in the early 20th century to supply water to the growing population of Tokyo. Today, the river is popular for activities like cycling, jogging, and picnicking.