The phrase refers to the critical connection points between Istanbul's two most vital arterial highways: the Otoyol 2 (O-2) and the E5 (D-100) . The Core Infrastructure
The "A E5" likely signifies the interchanges (labeled as "K" or "Kavşak" in Turkish) where these two massive systems meet to distribute traffic between the inner city (E5) and the outer transit routes (O-2) .
The roads typically intersect near Mahmutbey , a major junction where the O-2 meets the O-3 and links back toward the E5 .
The primary connection occurs at the Ataşehir/Ümraniye junction, allowing travelers to move from the outer ring road back into the heart of the Anatolian side . Comparison of the Two Routes Otoyol 2 (O-2 / TEM) E5 (D-100) Primary Use High-speed transit, heavy trucks Local commuting, Metrobus Bridge Connection Fatih Sultan Mehmet Bridge 15 July Martyrs Bridge Environment Northern outskirts, industrial Central urban residential/commercial Toll Status Toll-free (except for the bridge) Generally toll-free If you need a more formal technical paper,