Bursa

i.Mount Uludağ and the Bithynian Plain

Bursa is built on a long terrace at the foot of Uludağ — "the Great Mountain," 2,543 metres, the ancient Olympus Mysius, the highest peak of Marmara and the most visible landmark of the entire region. The mountain closes the city on the south; northward the land falls in a series of fertile terraces to the Bursa plain, then to the Sea of Marmara some thirty kilometres away. Hot springs rise along the foothill belt; the springs that gave Roman Bursa its early reputation as a spa town still feed the bathhouses (kaplıca) of Çekirge, on the city's western edge. To stand on the terraces of the Yeşil Türbe at twilight — the green-tiled mausoleum that crowns the Yeşil hill — and look westward over the city, with the snow-line of Uludağ above and the Marmara plain falling away below, is to understand at a glance why the Ottoman house chose this place as its first capital.

ii.Prusa — the Bithynian Foundation

The Greek-speaking city on this site was founded in the early 3rd century BCE by Prusias I, king of the small Hellenistic kingdom of Bithynia that controlled the southern shore of the Marmara from the death of Alexander until the Roman annexation of 74 BCE. Prusias named the city for himself: Prusa ad Olympum, "Prusa at the foot of Olympus," to distinguish it from the other Prusas of Hellenistic Asia. The Bithynian kingdom never grew large, but its capital at Prusa prospered modestly as a regional centre — Strabo, writing in the early 1st century CE, calls it "a well-built city, on the Hippios river that runs to the gulf of Cios."

iii.Roman and Byzantine Prusa

After 74 BCE Prusa passed with the rest of Bithynia into the Roman empire, becoming part of the senatorial province of Bithynia et Pontus. The younger Pliny was governor here in 110–113 CE, and his letters to Trajan from this province are one of the foundational documents of Roman provincial administration. Under the Byzantines the city kept its standing as a regional capital and a major bathing and military centre on the road between Constantinople and the Anatolian plateau. In the 6th century the emperor Justinian I built a palace and refurbished the bathhouses at Çekirge — the palace is gone, but the spa tradition continues. The medieval Greek form Prousa shifted, in Turkish mouths, to Bursa, the name the city has carried ever since.

iv.The Ottoman Conquest of 6 April 1326

The Ottoman emirate that captured Bursa was, when it began, the smallest of the dozen or so Turkmen beyliks that had risen on the post-Seljuk Anatolian frontier after the collapse of the Sultanate of Rûm in the late 13th century. Its founder, Osman Bey (d. 1324, the dynasty's name-source) had built up a small principality in the Bithynian hills above Söğüt, raiding the Byzantine border country and gradually taking the small fortified towns of the southern Marmara hinterland. The siege of Bursa began in 1307, in Osman's lifetime, and continued — by attrition rather than assault — through nearly twenty years.

The city fell on 6 April 1326, to Osman's son Orhan Gazi, who had succeeded his father two years earlier. The Byzantine commander Saroz handed it over by negotiation rather than storm; the Greek population was permitted to remain. The Valilik's official narrative — and the standard scholarly account in Heath Lowry's The Nature of the Early Ottoman State (SUNY Press, 2003) — emphasises that the conquest of Bursa was the moment at which the small Ottoman principality became, in any meaningful sense, a state: it gave the Ottomans their first city, their first administrative apparatus, and their first taxable urban economy. The date is observed annually as Bursa'nın Fethi, the conquest of Bursa.

v.The First Ottoman Capital — 1326 to the 1360s

From 1326 Bursa was the capital of the Ottoman state. Orhan made it his seat of government, and around the foot of the citadel he and his successors raised the four foundational architectural complexes (külliyeler) of the early Ottoman city. Orhan's complex (1339) — mosque, medrese, hamam, imaret, and the founder's tomb — established the pattern. Murad I's Hüdavendigar complex at Çekirge (1366), with its peculiar two-storey mosque-and-medrese in a single structure, refined it. Bayezid I's Yıldırım complex (1390s), east of the city, and Mehmed I's Yeşil complex (1421) on the eastern hill, finished it.

From around 1369 — after the conquest of Edirne (Adrianople) on the European side of the Marmara — Bursa shared the capital function with Edirne, and the imperial court increasingly campaigned from there. By the conquest of Constantinople in 1453 the political centre had moved on, but Bursa remained the dynastic and religious heart of the empire: the first six Ottoman sultans — Osman, Orhan, Murad I, Bayezid I, Mehmed I, and Murad II — are all buried here, in türbeler within the city's old quarters. The phrase used in the Ottoman chronicles for the city is yeşil Bursa, "green Bursa," for the gardens and water that wrapped the imperial mausolea.

vi.The Bursa Style — and the Inverted-T Plan

The mosque architecture that emerged at Bursa between roughly 1340 and 1430 is the first distinctively Ottoman building tradition, and it is known in the architectural literature as the Bursa style. Its most characteristic plan is the inverted-T (ters T) or "zaviyeli" mosque, in which the central prayer hall is flanked by two side chambers — originally used as guest-rooms for itinerant dervishes (tabhane) — that give the building, in plan, the form of an inverted T. The Yıldırım Camii, the Yeşil Camii, and the Muradiye Camii are the canonical examples.

The other Bursa-style innovation is decorative: the polychrome tile interiors for which the city's name became a byword. The Yeşil Türbe (the Green Mausoleum) and the adjoining Yeşil Camii (both 1421, for Mehmed I) are entirely revetted, inside and outside, in deep-turquoise (çini) tiles of the kind that the workshops of nearby İznik would later carry to imperial Istanbul. The Bursa-style tile programme is the direct ancestor of the great Ottoman tile traditions of the 16th and 17th centuries.

vii.The Silk City — Koza Hanı and the Trade

From the 15th century onward, Bursa was the silk-trade capital of the Ottoman world. The raw silk came overland from Iran along the long caravan road through Tabriz and Erzurum; the woven silk left Bursa for Italy, the Crimea, and Egypt. The historian Halil İnalcık, in his classic article "Bursa and the Commerce of the East" (JESHO, 1960), traced how the city's commercial archives — the kadi sicilleri (court records) preserved at Bursa — document the working of one of the largest silk markets of the early-modern world. The Koza Hanı (the Cocoon Caravanserai, 1490, built under Bayezid II) is the surviving heart of that trade: a two-storey court of arched rooms around a fountained courtyard, where raw cocoons were still being auctioned in the early 20th century.

The silk industry contracted under European competition in the 19th century, but Bursa textiles — and especially Bursa towels — remained a national specialty. The city's modern industrial economy is, in some sense, the silk economy's grandchild: today Bursa is Türkiye's automotive centre (Renault, Fiat-Tofaş, Karsan, and a dense network of component suppliers cluster here), with a manufacturing economy that places the province third or fourth in national industrial output.

viii.The Republic and the Modern Province

Under the Republic, Bursa kept its standing as the third or fourth city of Türkiye. The 1855 earthquake — a powerful M7.1 event that levelled much of the historic centre — had been the major disaster of the previous century; the 20th-century rebuilding largely respected the old street pattern of the four hills (Hisar, Yeşil, Yıldırım, Muradiye), with the Ottoman complexes still anchoring the older quarters. The metropolitan municipality today covers seventeen districts. Under the TÜİK 2024 address-based registration count the province population is roughly 3.2 million; the three central districts — Osmangazi (~885,000), Yıldırım (~655,000), and Nilüfer (~562,000) — together carry over two thirds of the metropolitan total.

Beyond the city, the province includes the ski-resort town of Uludağ (the busiest winter-sports centre in Türkiye), the lake-and-mosque town of İznik (ancient Nicaea, the site of the 325 and 787 ecumenical councils and the great Ottoman tile workshops of the 16th century), and the small Ottoman village of Cumalıkızık on the lower slopes of Uludağ — one of the seven surviving founders' villages around the early-Ottoman capital, and the only one inscribed by UNESCO alongside Bursa itself.

ix.UNESCO 2014 — Bursa and Cumalıkızık

In 2014, UNESCO inscribed Bursa and Cumalıkızık: the Birth of the Ottoman Empire on the World Heritage List as a serial property of eight component sites under cultural criteria (i), (ii), (iv) and (vi). The component sites cover the four imperial külliye complexes (Orhan, Hüdavendigar, Yıldırım, Yeşil), the citadel area with the Tombs of Osman and Orhan, the Hanlar Bölgesi (the commercial quarter centred on the Koza Hanı), the Sultan Murad II/Muradiye complex, and the Ottoman village of Cumalıkızık. The inscription rationale singles out the Ottoman use of the vakıf (public-endowment) system and the ahi (guild-brotherhood) network as the urban-planning innovations that produced this specific city form — and identifies the "Bursa style" inverted-T mosque plan as the architectural type for which Bursa is the type-site.

x.What to See, in Order

The walking shape of historic Bursa runs east-west across four hills. The eastern starting point is the Yeşil hill: the Yeşil Türbe (1421) and the adjacent Yeşil Camii, with the small Türk ve İslâm Eserleri Müzesi next door. West from Yeşil, the route runs down past the Emir Sultan Camii and the open Setbaşı bridge over the Gökdere into the central commercial district — the Hanlar Bölgesi, where the Koza Hanı (1490), the Emir Hanı (1339, the earliest surviving Ottoman han), and the great Ulu Cami (1399, twenty-domed, Bayezid I) stand within five minutes of each other. From the Ulu Cami the route climbs to the Hisar — the small Byzantine citadel that became Orhan's first palace — and the Osman Gazi ve Orhan Gazi Türbeleri, the founders' tombs, on the citadel terrace. Further west still are the Muradiye complex (Murad II, 1426) and, at Çekirge on the western edge of the city, the Hüdavendigar complex (Murad I, 1366) and the hot springs.

For the Ottoman village component of the UNESCO property, a half-day excursion from the city reaches Cumalıkızık — fifteen kilometres east, on the lower slopes of Uludağ — with its restored 13th- and 14th-century stone-and-timber houses lining narrow cobbled streets. For Uludağ itself, the cable car from the eastern edge of the city reaches the upper station in twenty minutes; from there the open-air paths run to the summit ridge at 2,543 metres. The lakeside town of İznik, an hour's drive east, is the natural day excursion of the second visit.

The first Ottoman city — given its shape by the four founder-sultans whose tombs still anchor it, and named, in the imperial chronicles, simply yeşil Bursa, "green Bursa."

For the Ottoman "second capital" in Thrace that took the imperial function after 1369, see Edirne. For the imperial capital that succeeded both, see İstanbul. For Türkiye's geography in the wider sense, visit our sister site CountryOfTurkey.com.