Mount Athos is a conspicuous example of segregated space - a place where males and females dare not mix. In a world where even unisex restrooms are beginning to make their mark, single sex space is a diminishing province. Convents, monasteries and prisons apart, it is ever rarer nowadays to come across a space that is exclusively reserved for just one gender. Of course there are the exceptions that buck the trend. In Japan, Skymark Airlines (www.skymark.co.jp) have one section of the cabin on certain domestic flights reserved exclusively for women. No European airline has emulated this Japanese innovation, though there are a growing number of women's hotels, such as the Intermezzo (www.hotelintermezzo.de) and the Artemisia (www.frauenhotel-berlin.de) in Berlin.