In the flower-power period of the last century (from 1970) hippies tried to find their way to Holy Mountain, seeing the similarities between Hesychasm and religions in the far East.
Here a picture of a hippie on the boat to Athos, still having long hair.
But the hippies did not get a chance and tried in vain to settle on Athos, because before they could collect their Diamoniterion they had to cut their long hair and they had to leave after three nights!
In that time visitors to the Holy Mountain, before visiting to the Minsitery of Northern Greece, had to go to their national Embassy or Consulate, where you would have to bring a letter of recommendation and show that you were ‘man of good faith’. After that you met the famous mss. Kalivapoulou in the Ministery.
The same hippies (Dutch guys from Friesland, at that time 26 year old, thanks for providing the pictures!),made this picture of the Protaton in 1973.