The place has a great view over Helsinki and is worth a visit. I bet sunrise is the best time to visit this one, but anytime has great views.
The area has some landmarks that had a great significance in World War II regarding the safety of citizens of Helsinki. You'll find a bit more information on the spot.
How to get there?
You can travel with a local train or by bus. If you take the train, get off at "Oulunkyla" -station. It takes about 10 minutes from the main train station.
You can also take the bus #69 and jump off at "Oulunkyla" train station, or the stop right before the station.