New York — Alex von Furstenberg’s Southampton house is a haven for hedonism.

The 35-year-old heir has been hosting the hottest parties of the summer, in which droves of models are often talked into removing their tops – or running the risk of not being invited back.

The Euro playboy has taken to shooting Polaroids of his topless guests, and, according to one visitor, now keeps a stack of them in the kitchen of his three-bedroom bungalow on Flying Point Road.

“It’s an orgiastic scene,” one male guest divulged.

Regular visitors to “Alex von’s” house include fashion designer Jamison Ernest, his supermodel girlfriend Anna K., club promoter Justin Melnick, and a regular rotation of stunners who are all expected to indulge in pastimes like topless barbecues and strip backgammon.

After a night of swinging house activities, groups of wine-sozzled guests often collapse into bed naked together.

In fact, the festivities got so boisterous that more space was needed – so two models were hired to drive a rented Winnebago to be parked in the driveway.