Otoyol 21A

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O-21A
Route information
Part of E90
Length32 km (20 mi)
Existed1992–present
Major junctions
West end D.330 / D.750 near Tepeköy, Konya
East end O-21 near Eminlik, Niğde
Location
CountryTurkey
RegionsCentral Anatolia
ProvincesKonya, Niğde
Highway system
O-21 O-22

Otoyol 21A, abbreviated as O-21A, is a 32 km (20 mi) long auxiliary otoyol connecting the D.330 and D.750 to the O-21. The motorway was opened in 1992 as a connecting route to Konya and passes through mostly uninhabited rural land. The O-21A is a part of the E90.

The motorway was deemed too short to receive its own O-XX designation, despite being longer than the O-50, but too long to be designated as an exit; therefore, the route was signed as the O-21A, and is the only otoyol route in Turkey to have an alpha-numeric route designation.