Notre-Dame de la Garde - A Symbol on the Edge

S1, E1: Every year, over two million visitors climb up to Marseille's most-visited monument, Notre-Dame de la Garde basilica. How did this structure, which has stood up to so much, see the light of day? With the help of historians, architects and experts, we shall unravel the secrets of the construction of this indestructible monument whose builders had to be exceptionally resourceful.