The middle sector is the most technical and visually stunning. It includes the infamous Castle Section (Turns 8 to 11), where the track narrows to just 7.6 meters wide —the narrowest on the F1 calendar. Drivers must thread their cars through a steep uphill climb alongside the 12th-century Fortress Walls of Icheri Sheher.

A unique feature visible only to the initiated is the gradient changes. The map is flat, but the terrain is not. The circuit features a steep uphill run towards Turn 13 and a significant downhill section at Turn 15.

Combined with the anti-clockwise layout, this makes Baku one of the most physically demanding races for drivers. The G-forces pull their heads to the right for the majority of the lap, straining the left side of the neck. By the end of the race, fatigue sets in, and that is precisely when the walls tend to reach out and bite.