Either hike, run, climb or ride up, the view over the city is certainly worth it. Bastille lets you escape the city for just a moment, you'll feel like you're miles away in the nature. Sundays are usually crowded when families go there for a walk after lunchtime. During the week you'll mostly see runners and couples looking for a romantic view.
View Gallery
View Gallery
This is the most important landmark of Grenoble. You can take the cable car from Jardin du Ville or walk up the stairs starting at Jardin des Cairns (takes about 45 minutes) and admire the surroundings. At the top you'll be rewarded with a 360 degree view of Grenoble which is definitely worth your efforts.
If you're into climbing take the Viaferatta route. You can rent the equipment in town and climb half or all the way to the top.