Autopista AP-51
Autopista Ávila - Villacastín
Route information
Length	24 km (15 mi)
Major junctions
From	Villacastín
To	Ávila
Location
Country	Spain
Highway system
Highways in Spain Autopistas and autovías National Roads

The Autopista AP-51 (also known as Autopista Ávila - Villacastín and Conexión Ávila) is an autopista in the community of Castile and León, Spain. Opened in late 2002, it runs for 24 kilometres (15 mi) between the Autopista AP-6 at the village of Villacastín, in the province of Segovia, and the eastern outskirts of the city of Ávila.^[1] It runs parallel to the N-110. As a toll road, it is operated by the Abertis Group.^[2]

Upon reaching Ávila, the highway then runs for a further 9 kilometres (5.6 mi) as an autovía, the A-51, forming a partial beltway around the north of Ávila and connecting with the Autovía A-50.