Late last year, BOB ADAMS set out to walk the length of the River Foss, starting from York's Blue Bridge. On the final two days of the walk, completed this summer, he encountered naughty nuns, mischievous monks, and a secret reservoir

My walk along the length of the River Foss, completed in stages over the last year, was nearing its end. I reckoned just two more days should see me to the river's source.

The first of those days, completed in July, was a gentle four-mile stroll around the village of Stillington. I headed south along the York road to cut through to St John’s Well and its chalybeate spring (chalybeate meaning that the water contains iron salts and has healing properties) before heading east to the site of Moxby Priory, then back to the village via the old mill.

Moxby Priory was established as an Augustinian nunnery in the 12th Century. The original priory was at Marton, two miles to the north. It was established as a ‘double-house’, in other words accommodating nuns and monks together. But this could only lead to trouble so Moxby was founded some years later.

But where there’s a will there’s a way. In 1310 nun Sabrina de Apelgarth was apostatized, in other words excommunicated, for sexual misdemeanours. She was received back into the church in a state of penitence. But eight years later Archbishop Melton visited and stated that anyone found guilty of incontinence, meaning the sexual variety, was not to remain in office.

But the monks at Marton were no better. In 1314 Brother Roger was deemed to be too friendly with the ladies. His penance was to eat vegetables on a Wednesday and he was forbidden from speaking to women. Harsh punishments indeed!

In 1322 the Scots under Robert the Bruce devastated the countryside after defeating the English at the Battle of Scawton Moor. The nuns escaped to Nun Monckton. Three years later the prioress of Moxby, Joan de Barton, had to resign after being found guilty of super lapsu carnis with the chaplain. Her punishment was to be shut up in a room by herself for a year. Doesn’t seem fair when we consider Roger’s punishment.

Enough of monks and nuns, what about the walk?

Well I did find St John’s Well, now a nondescript boggy area at the edge of a small wood. The walk along the ‘Stripe’ towards the Priory was delightful, following the stream through a copse of trees. I tried to persuade myself that the water was reddish-brown in colour, in other words containing iron. I did not test it for healing properties.

Of the Priory, now Moxby Hall Farm, there was nothing to be seen, apart from some earthworks that used to be fishponds.

I followed Skeugh Lane back to Stillington Mill, where the planned canal from York was meant to end. The mill, formerly a corn mill, still contains its original wheel and can now be booked for weddings.

Day two of my final leg of the walk, completed in mid-August 2019, took me to the highest reaches of the Foss and finally to its source, above Oulston Reservoir. My friend Steve joined me on this walk, around nine miles. His wife kindly dropped us off at the tiny hamlet of Marton-in-the-Forest and picked us up at the end, at the village of Yearsley, high up in the Howardian hills.

We started at the tiny church which we agreed had a 'very special and peaceful ambience’, as described on its website. After a few hundred yards we continued northwest along Harryfield Lane to the site of Marton Priory. It is now a farm but you can still make out the stone footings of the original medieval buildings. We spotted some stone heads and a coat of arms embedded around the farmhouse door, not sure if they were original. Centuries ago the Foss was diverted to supply a complex of fishponds as well as a mill.

As we proceeded north the village of Crayke began to dominate the view ahead. We ascended to the top of the hill along lanes barely changed in centuries.

The monastic tradition clearly once dominated this area. Saint Cuthbert of Lindisfarne founded a monastery on the hilltop, long before the castle and church were built. The present church was built in 1436 and the castle in 1450. Inside the church is a magnificent banner created in 1996 by the villagers. It depicts local history, industry and social activities in multi-coloured, three-dimensional textiles.

Steve likes to eat early so we had our sandwiches in the churchyard gazing at the Vale of York stretching for miles south towards the cooling towers of Drax and Ferrybridge. I understand that the Ferrybridge towers may soon be no more.

This whole area was known for centuries as the Forest of Galtres which, according to Wilson’s 1870 Imperial Gazeteer, was once a mixture of forest, moor and bog, tenanted by wild beasts and haunted by robbers, stretching about 15 miles from York City walls northwards to Craike-Hill.

After Crayke we took the Brandsby road down the hill, turning off at Mill Green Bridge to head north along various paths and tracks. Buzzards circled above us calling to each other with their high-pitched screeches. We crossed cornfields damaged by the recent heavy rainstorms and peeped into what looked like a deserted farmhouse that still retained a beautiful garden in full summer flower.

After crossing the last remnants of the Foss by stepping stones we headed up the hill to Oulston Reservoir. This quite large expanse of water was created by the building of a dam in the 1790s by a Mr Scruton, who also completed the construction of two locks and the canal bridge at Strensall. The aim was to provide water for the canal during the summer months. It is now a beautiful place, its waters reflecting patterns from the clouds above and the mature trees surrounding its banks. Steve caught a tiny frog.

My initial impression was that we had arrived at our destination but, on a closer study of the map, I realised we had further to go. The original river continued up a tiny ravine choked with vegetation to a spring situated next to the road from Yeasley to Oulston. After much scrabbling through briars and stinging nettles (in shorts) we eventually found what we thought was the original spring, a place where the depression caused by the stream ended. It was dry.

It was then a short walk across fields to the village of Yearsley and our lift home.

My exploration of the Foss from confluence to source completed, my next river will be the Derwent. In fact I have already started. Watch this space...

Bob Adams' book 'Power and Conflict in Eighteenth Century India', in which he traces the footsteps of his ancestor Solomon Earle, a Captain in the East India Company army in the late 1700s, is now available from ypdbooks.com in print (£10) or as an e-book (£3.99)