The monastery in itself, although very old, is not really worth the climb - you cannot see much of it either, as it is still inhabited. But what is wonderful is to go to Kaisariani as all Greeks do, for the outing in the fresh, wooded slopes of Mount Hymettus, so peaceful and relaxing, although only a few minutes from the hustle and bustle of the polluted, congested city. You can take a walk and breathe the fresh air, take in the stunning views of all of Athens, including the sea at a distance, or sit down for a picnic (there are special tables/benches). The wood is not left to its own resources: it has been replanted after the fires of many years ago, and generally taken care of, so it's really a pleasure to spend a few hours there - you will walk or drive down feeling renewed!
Unfortunately, the lovely cool spring from which I used to drink in my childhood now has been condemned, because its water is no longer safe - a source of sorrow every time I pass by it.
Careful, the whole place is closed from sunset to sunrise.
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