Go try it you'll never fly straight and level again.
The main challenge is soaring, followed by going places. On a good day duration is limited by daylight or your bladder and dsitance by your courage.
The following sites will give you more info, they are for my home club at Aboyne and the British Gliding Association respectively.
http://www.gliding.co.ukhttp://www.deeside.glidingclub.co.uk