As you can see in the pictures, the Willy path leads into the mountains to the right before the stairs. It's a nice path, but it doesn't lead to the Müggelturm or directly to the Großer Müggelberg.
However, this staircase connects the former, unfortunately no longer existing Marienlust restaurant with the Müggelturm. Anyone who has managed the 217 steps (actually 220 if you count the three steps in front of the stairs) will be rewarded with a beautiful view of the forests and the Long Lake. The stairs are officially closed from November to March, but they are only really impassable when the steps are icy.
In addition, the café on the first level and the large restaurant on the second level at the foot of the Müggelturm now invite you to linger.
Rob Ert: That's not the highest point yet. The mountain on which the Müggelturm stands is only 88 meters high. The highest natural elevation in Berlin, the Große Müggelberg, is about one and a half kilometers further east.