Strenous but worth the effort
It will take you about 45 minutes to get to the summit with some of the climb on chunky stone stairs, other bits along a more gradual dirt trail. You’ll pass some small shrines along the way and also get some good vistas to the left and right as you climb.
The summit is home to a temple (don’t forget your sarong) and the best viewpoint is out to the north. In a rather bizarre twist, the day we wandered (or rather, staggered) to the summit, we found a tall westerner standing at the photo point stark naked. Suffice to say that struck us as a little odd.
Aside from nude westerners, the temple and the trail to the summit is overrun with monkeys.
If you’ve got time up your sleeve, this is worth a look, but be warned, it is a strenuous climb and best not undertaken in the middle of the day without water!