The Olza River is a river located in southern Poland and northern Czech Republic. It is a tributary of the Odra River, flowing through the Silesian region. The river is approximately 90 kilometers long and plays an important role in the local ecosystem and water management. The Olza River is known for its picturesque landscapes and diverse wildlife. It serves as a natural border between Poland and the Czech Republic in some areas. The river is also popular for recreational activities such as fishing and kayaking, attracting both locals and tourists to its banks.