Mostar interchange or colloquially Mostar (Serbian: Мостарска петља, translit. Mostarska petlja) is one of major interchange and a surrounding urban neighborhood of Belgrade, the capital of Serbia. It is located in Belgrade's municipality of Savski Venac.
The Mostar looped interchange was constructed in 1974, as one of two major ones (the other one being Autokomanda) on the highway Belgrade–Niš. The highway runs right through the urban centre of Belgrade, which is still an issue of debate even though the road was originally intended as a fast, intercity Bežanija-Autokomanda freeway. The interchange itself was built on the location of the old neighbourhood of Jatagan Mala. Construction began in 1967 and some technical specifications of the interchange include:
Due to its construction, Mostar incidentally serves as a water collector so during the major rains it gets regularly flooded by the pond created by the rainwater.
A bitter dispute between the mayor of Belgrade, Nenad Bogdanović and a group of architects from the previous city's establishment (including the construction of Mostar and Auto Komanda) resulted in mayor's description of the interchanges from October 2006: 'Those are the two worst interchanges and the only ones in the world with traffic lights...people who made those are today criticizing us.'
The surrounding neighbourhood is almost entirely non-residential. The northern side is occupied by the buildings of the Ministry of the Interior (destroyed in the 1999 NATO bombing of Serbia) and the Clinical Centre, which is the largest clinical complex in Belgrade. The southern side comprises the 'BIP' brewery, the Belgrade Centre railway station in Prokop, a series of half-ruined storages and former factories and the facilities of the Belgrade Fair. In south it borders the neighborhood of Senjak. To the west it continues into the Belgrade-Niš highway and to the east to the Novi Beograd and further to Belgrade-Zagreb highway (over the Gazela bridge). The ruined old mill south of the loop was completely renovated and updated with the additional two new buildings. Today it is location of the Radisson Blu Old Mill hotel.