Estate agents Rettie & Co have been instructed by trustees of Sancta Maria Abbey at Garvald, East Lothian, to market Nunraw Tower and its 138-acre grounds for offers over £2 million.
One of the UK's largest Cistercian communities lives at the nearby Nunraw Abbey and the Abbot moved to reassure pilgrims the Order would continue to offer stays for spiritual guidance or rest that will be "closer to monastic life".
The tower, which will need adaptation and investment to return it to family living, is originally believed to date from the 16th century when a tower house was recorded as being built by the Hepburn family.
The original tower house is now incorporated into the Baronial mansion built in red sandstone by the Dalrymple Family in 1860.
In 1946 the Cistercian Monks returned to Scotland for the first time since the Reformation and made Nunraw their home.
The tower became the foundation of the monks and in 1952 they began building the Sancta Maria Abbey to the south-west of the tower, which will be where pilgrims will now stay.
Nunraw Tower is listed Category A alongside the garden Sundial and 16th Century Beehive Doocot. The North Lodge and Gate are listed Category B.
Rettie said the tower "stands in delightful gardens". The agent also said the tower has "exceptional architectural character and scale and East Lothian residential estates of the stature and quality of Nunraw come to the market infrequently".
The Abbey is one of four Cistercian Abbeys in the UK and about 50 monks are based in East Lothian.
Abbot Dom Mark Caira said the sale was part of a "down-sizing" operation at Nunraw and although it will mean fewer guests will be able to enjoy a retreat at one time, their experience will be "closer to the monastic life within the abbey itself."
He said. "We are making the move to conserve our energies and use our facilities as best as we can."