After a fun ride in the téléphérique, or a steep, hour-long climb, the reward is a magnificent mountain panorama from Grenoble's stocky fortress, built during the first half of the 19th century to strengthen the city against Alpine rival the Duchy of Savoy. On the viewing platform known as the Belvédère Vauban, panels (in French and English) indicate what you're looking at. On clear days you can see not only the peaks of the Vercors but also the snowy hump of Mont Blanc.
The fort complex has its own tourist office, a couple of places to eat, and a number of walking trails, including the GR9, start or pass by.