Mudurnu is a district of Bolu province, located in the Western Black Sea subregion of the Black Sea Region. The district center is situated in the valley between Hisar and Kulaklı hills, 50 km southwest of Bolu. With its geographical location between 40°19' - 40°39' north parallels and 30°50' - 31°30' east meridians, it borders Düzce in the north, Bolu center in the northeast, Nallıhan in the south, and Göynük and Akyazı districts in the west. The district, which lies 840 meters above sea level, has an area of 1,349 km². According to TÜİK 2024 data, its population is 18,360.

^{Clock Tower (Mudurnu Belediyesi)}

History

Mudurnu is an ancient settlement with history dating back to the Hittite and Phrygian periods. Its first settlement site was Hisar Hill, to the east of today’s town. The castle, built by Matarni, daughter of the Byzantine governor of Bursa, gradually took the names "Modrones," "Moderna," and "Mudurlu," eventually transforming into its current name, "Mudurnu." The first Ottoman raider to arrive in the region in 1292 was Samsa Çavuş, whose grave is believed to be in Samsaçavuş Village. The district was incorporated into Ottoman lands in 1307. Administratively, it was connected to Bursa between 1307-1324, to Bolu Sanjak between 1324-1811, to Kastamonu Sanjak in 1865, and with the Republic in 1923, it became a district of Bolu.

Geographical Structure

Mudurnu, a district of Bolu province, is located in the Western Black Sea section of the Black Sea Region. It is situated between 40°19' - 40°39' north parallels and 30°50' - 31°30' east meridians. It borders Düzce in the north, Bolu center in the northeast, Nallıhan in the south, and Göynük and Akyazı in the west. Situated 840 meters above sea level, the district covers an area of 1,349 km². Its rugged terrain is surrounded by ranges such as the Abant Mountains (Erenler Peak: 1,794 m), Sülük Peak (1,767 m), and Hisar Mountain (1,384 m). Due to its flysch formation, landslides are common, and it lies within the first-degree earthquake zone. The main water sources are the Mudurnu Stream, which flows into the Sakarya River, Lake Karamurat (20-25 km²), and Lake Sülük (35-40 km²). The Mudurnu Plain has low fertility, and due to climate conditions and insufficient irrigation, its agricultural productivity is limited.

Climate and Vegetation

Mudurnu has transitional climatic characteristics between the Black Sea and Central Anatolia climates. It receives an annual average of 550 mm of precipitation, most of which falls as snow during winter. There are an average of 88 summer days. Forests cover 65% of the district’s area (87,558 hectares), offering a rich variety of plant species: Scots pine, black pine, fir, oak, beech, hornbeam, and chestnut are the main tree species. In the undergrowth vegetation, boxwood, heath, and rhododendrons are widespread. Even among cultivated fields, patches of forest are found.

Civil Architecture

Mudurnu, which has been declared an urban conservation site for preserving its traditional character, hosts 231 registered structures (207 houses, 20 religious buildings, 2 military structures, 2 natural monuments). The 2-3 story wooden houses are characterized by cellars, kitchens, and oven rooms on the ground floor, and sofaed rooms on the upper floors. Jettying (cumba), oriel windows (şahnişin), and wooden carvings (door, window, balcony designs) are distinctive features. The Armutçular and Haytalar Mansions, with their four-story structures, rooftop observation towers (cihannüma), 15-17 rooms, and magnificent ceiling craftsmanship, stand out. The houses have hipped roofs covered with traditional red tiles, and their chimneys are aesthetically designed.

^{Mudurnu Houses (Mudurnu Belediyesi)}

Culture and Tourism

Thermal Springs

The district has two important thermal water sources:

• Babas Thermal Spring: Located 3 km from the district center, its 40°C water is beneficial for rheumatic diseases. It is the only regional source that does not require cold water mixing. It operates in an old building with 8 rooms.
• Sarot Thermal Valley: Located in the town of Taşkesti. With water at 66°C, it is effective for kidney and urinary tract diseases when taken as a drinking cure, and for rheumatic diseases when used for bathing. It has a capacity of 4,500 people daily.

Historical Monuments

Mudurnu hosts architectural treasures from the early Ottoman era:

• Clock Tower (1890-1905): Rebuilt with stone after a fire, constructed by prisoners. It is 12 m high and has a 185 kg bell.
• Mosques: Yıldırım Bayezid Mosque (1374; 19.65 m dome span), Suleiman the Magnificent Mosque (1546; Seljuk-influenced wooden ceiling), Samsa Çavuş Mosque (early Ottoman period), Orhan Bey Mosque (1920s).
• Yıldırım Bayezid Bath (1382): Stands out with its geometric ornaments and its balıklı kurna (stone basin in a Turkish bath) Its architect is recorded as "Ömer, son of İbrahim" in its inscription.
• Mudurnu Castle: An octagonal structure from Byzantine times. Other archaeological remains include Cinler Hill in Çevreli Village, the ruins of Asartepe in Taşkesti, as well as tumuli in Gedikler and Pelitözü.

^{Süleyman the Magnificent Mosque (Mudurnu Belediyesi)}