Those using the Bolu Mountain Tunnel towards Istanbul should be careful! It will be closed during these hours.

Highway crews started paving work this morning at the Bolu Mountain Tunnel crossing of the Anatolian Highway, the most important transit route between Ankara and Istanbul.

Due to the work, the Istanbul direction between the Abant and Kaynaşlı toll booths, which also includes the Bolu Mountain Tunnel passage, will be closed to traffic between 10:00 and 15:00 on weekdays between 13-31 October.

In a statement, the Bolu Governor's Office said, "Due to the coating work to be carried out at the tunnel portal mouth in the direction of Istanbul between the Abant Junction and Kaynaşlı Junction at the Bolu Mountain crossing of the Anatolian Highway (including the Bolu Tunnel), the direction of Istanbul will be closed to traffic between 10:00 and 15:00 on weekdays, starting on Monday, October 13, 2025. The work in question is planned to be completed on Friday, October 31, 2025, and during this period, drivers will be directed to the D-100 State Road from the Abant Junction and will be able to reconnect to the highway at the Kaynaşlı Junction."

Source: DHA