EVERYWHERE you go in East Lothian there are ancient monuments to the county’s past.

Whether it is a prehistoric fort on top of a hill, a tooth-embedded stone cairn from the Bronze Age or a burial ground, evidence of those who came before us is easy to uncover.

Sometimes there is nothing evident to the naked eye and what looks like an arable field or woodland was actually once a site of huge importance.

One such fascinating site is the former St Mary’s Nunnery, established near Abbey Mill Farm, Haddington.

The nunnery was founded by Countess Ada de Warenne, a Scottish princess who produced two of the nation’s kings.

Countess Ada was married to Henry of Scotland and granted the privileges of Haddington and other areas in East Lothian by her father-in-law King David I.

Henry died the year before his father, who made arrangements for the couple’s son Malcolm to take the throne when he died.

As a result, Ada found herself ruled by her 12-year-old son, King Malcolm IV; then, after his untimely death at the age of just 24, by her younger son William the Lion, who would be Scotland’s longest-serving king prior to the Union of the Crowns in 1603.

No longer needed in the maternal role, the still-young dowager countess Ada retired to her lands in Haddington and devoted her time to good works.

She gave land to the Cistercian Nuns and helped found their convent, which was dedicated to St Mary, and is said to have inspired the name Nungate.

It was one of the largest nunneries in Scotland and was established between 1152 and 1159. At its peak it is thought to have had fish ponds as well as gardens.

The nunnery would be burned to the ground twice in the next four centuries by the English and closed in the early 17th century after the Reformation.

Even after surviving two blazes, the nuns were forced to seek royal protection in 1471 amid claims the Lairds of Yester and Makerston “ungallantly seized their lands”.

The last prioress was called Elizabeth Hepburn and stood her ground in 1548 when the English invaders came.

Although they took the town of Haddington, the nunnery remained in Scottish hands and was where the Treaty of Haddington was signed in July that year, promising Mary Queen of Scots to Dauphin Francis in marriage in return for French help.

In a twist, the nunnery was built about a kilometre east of St Martin’s Kirk and the road which connected the two was known as Nun Gait, later becoming Nungate, where John Knox, the architect of the Scottish Protestant Reformation, lived in the 16th century.

A survey of the site in April 2013 reported that, although there were no obvious remains of the nunnery, there was an L-shaped anomoly on the land south of the graveyard which still sits there and traces of outlying buildings.

In 2016, Historic Environment Scotland reported it as a scheduled monument which it said was partly visible as a burial ground with a large mound next to it.

The agency described the site as a monument of national importance.

Its statement of scheduling said: “The monument is of national importance because it has an inherent potential to make a significant contribution to our understanding of the past, in particular of medieval ecclesiastical foundations and, more specifically, Cistercian establishments and medieval nunneries.

“The monument was one of the richest nunneries in Scotland, with connections to lands across central Scotland and pioneering land management and exploitation activities.

“The monument is a rare survival, with high potential for the good preservation of buried features and deposits, including architectural remains and burials.

“The monument is directly associated with Ada de Warenne and with significant historical events such as the Rough Wooing.

“It has the potential to make a significant contribution to our knowledge of the role of women in medieval religious life in Scotland, particularly in relation to monasticism.

“The loss of the monument would significantly diminish our future ability to appreciate and understand nunneries in Scotland and their role in respect of their local economies.”