The sign saying 'Mudmelong' was a gift to George Morton from his family on his 76th birthday.

"It must have taken considerable effort by someone with a ladder, cordless driver and the necessary bits to suit the long screws that attached it," Mr Morton said.

"The thief even took the screws!"

The sign had been up for just over a week before it disappeared.

It was designed to conform with the old gold mining heritage of the area from pre-rusted steel plates and black corrugated iron.

Mr Morton has lived on the property for most of his life and was thrilled with the present to replace his old tattered sign.

"Just why anyone would want to take it is beyond me, as the name Mudmelong is indigenous to that area as part of the old Araluen gold fields and is marked on maps as such," he said.

The police have suggested the sign may have been stolen to decorate a man cave or as a prank.

The sign was taken from the gate at 5399 Araluen Road, Lower Araluen, between between April 1 and 12.

Police are seeking any information residents have about the disappearance of the sign.

Contact Braidwood Police on 02 4842 2101 if you have any information.