State road D.400 (Turkey)

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D.400
Route information
Part of E90
Length2,057 km (1,278 mi)
Major junctions
West endDatça
East end Road 16 at Serow, West Azarbaijan
Location
CountryTurkey
Highway system
State road D400 near Şanlıurfa
Between Kumluca and Kemer (Antalya Province)
In Antalya as Dumlupınar Bulvarı
Between Yeşilovacık and Silifke (Mersin Province)
Boğsak Tunnel (Mersin Province)

D.400 is an east–west state road in southern Turkey. The 2,057-kilometre (1,278 mi) road starts at Datça in the southwest corner of the Anatolian peninsula and ends at the Iranian border at Esendere.

D.400 runs through the cities of Marmaris, Fethiye, Antalya, Alanya, Mersin, Adana, Gaziantep, Şanlıurfa, and Hakkâri and links to Road 16 in Iran. Between Nizip and Cizre, D.400 is part of the European route E90.