Filyos Stream; It is the tea that the streams coming from Köroğlu Mountains, Bolu Mountains and Ilgaz Mountains are collected and brought together. The tea, stretching for 228 kilometers, pours into the Black Sea in the town of Filyos in Zonguldak. The valley in which it is located offers various tourism opportunities with its flora and fauna diversity, hosting bird species and being suitable for activities such as rafting and angling.