Behind-the-Scenes Eiffel Tower Tour Including Champ de Mars’ Underground Bunker. Go behind the scenes at the Eiffel Tower and discover the places that few visitors get to see! On this intriguing 1.5-hour Eiffel Tower tour, explore the Champ de Mars’ underground bunker, and visit the engine room that controls the tower’s important hydraulic lifts. Head up to the 2nd level and enjoy privileged views from the rooftop terrace at the esteemed Alain Ducasse restaurant, Le Jules Verne. Book and Save 5% Off Behind-the-Scenes Eiffel Tower Tour Including Champ de Mars Underground Bunker.