6,2 km route 1 km underground (tunnel). One of stations under the ground.

After five and a half years of work conducted by VINCI Construction Grands Projets, the 3B section of the Cairo metro in Egypt is now open.

https://www.vinci.com/vinci.nsf/en/news-update/pages/opening_a_new_metro_line_in_cairo_egypt_042024.htm