The Old Bridge area of the Old Town of Mostar, with its exceptional multicultural (pre-Ottoman, eastern Ottoman, Mediterranean and western European) architectural features, and satisfactory interrelationship with the landscape, is an outstanding example of a multicultural urban settlement. The qualities of the site’s construction, after the extremely ravaging war damage and the subsequent works of renewal, have been confirmed by detailed scientific investigations. These have provided proof of exceptionally high technical refinement in the skill and quality of the ancient constructions, particularly of the Old Bridge. Of special significance is the Radoboija stream, which enters the Neretva on its right bank. This provided a source of water for the growing settlement, and from it springs a number of small canals used for irrigation and for driving the wheels of water-mills.
There has been human settlement on the Neretva between the Hum Hill and the Velez Mountain since prehistory, as witnessed by discoveries of fortified enceintes and cemeteries. Evidence of Roman occupation comes from beneath the present town.
Little is known of Mostar in the medieval period, although the Christian basilicas of late antiquity continued in use. The name of Mostar is first mentioned in a document of 1474, taking its name from the bridge-keepers (mostari ); this refers to the existence of a wooden bridge from the market town on the left bank of the river which was used by soldiers, traders, and other travellers. At this time it was the seat of a kadiluk (district with a regional judge). Because it was on the trade route between the Adriatic and the mineral-rich regions of central Bosnia, the settlement spread to the right bank of the river. It became the leading town in the Sanjak of Herzegovina and, with the arrival of the Ottoman Turks from the east, the centre of Turkish rule.
The town was fortified between 1520 and 1566, and the bridge was rebuilt in stone. The second half of the 16th century and the early decades of the 17th century were the most important period in the development of Mostar. Religious and public buildings were constructed, concentrated on the left bank of the river, in a religious complex. At the same time many private and commercial buildings, organized in distinct quarters, known as mahalas (residential) and the bazaar, were erected.
Of the thirteen original mosques dating from the 16th and 17th centuries, seven have been destroyed during the 20th century for ideological reasons or by bombardment. One of the two 19th-century Orthodox churches has also disappeared, and the early 20th-century synagogue, after undergoing severe damage in the Second World War, has been converted for use as a theatre. Several Ottoman inns also survive, along with other buildings from this period of Mostar’s history, such as fountains and schools.
The administrative buildings are all from the Austro-Hungarian period and have neoclassical and Secessionist features. A number of surviving late Ottoman houses demonstrate the component features of this form of domestic architecture – hall, upper storey for residential use, paved courtyard, and verandah on one or two storeys. The later 19th-century residential houses are all in neoclassical style.
Some early trading and craft buildings are still existent, notably some low shops in wood or stone, stone storehouses, and a group of former tanneries round an open courtyard. Once again, the 19th-century commercial buildings are predominantly neoclassical. A number of elements of the early fortifications are visible. The Hercegusa Tower dates from the medieval period, whereas the Ottoman defences are represented by the Halebinovka and Tara Towers, the watchtowers over the ends of the Old Bridge, and a stretch of the ramparts.