ON A hill top at one side of a wooded valley sits an octagonal tower.

Built in the mid-1730s, the mellow stone building, visible through a break in the trees, is a splendid sight, picked out in the afternoon sunshine.

On the opposite side of the valley sits an altogether more unusual structure - a mirrored ball on top of a metal construction with ‘windows’ of different shapes. Recently installed, it too catches the light, gleaming as it reflects it back across the valley.

Almost 290 years apart, the two distinctive sights are follies, one traditional, one modern - both an intriguing, quirky, part of the landscape. They stand in the beautiful setting of Studley Royal Water Garden, the serene series of ponds and a lake adjoining the dramatic remains of Fountains Abbey, together making up a World Heritage Site.

The Gazing Ball is one of four new creative works sited in the water garden as part of the National Trust’s art in the garden programme Folly!

Now in its third year, folly! encourages visitors to explore the Georgian water garden as it was originally intended; as a site of play and intrigue, with dramatic views that criss-cross the landscape.

The water garden is dotted with historic follies, fanciful structures designed to catch the eye, and for 2018, artists and architects have reimagined the garden’s lost follies which have long-disappeared from the landscape.

By Lucy and Jorge Orta, the Gazing Ball - on the site of a former Rotondo - dazzles with a mirror-like shine reminiscent of the moon ponds in the valley.

Of the four follies this is my favourite, especially seen from below across a bank of terraced laurel resembling a tea plantation.

I also liked The Cloud at Silver Pond, designed by 11-year-old Foster Carter, of Catterick Garrison, as part of a primary schools’ competition organised by North Yorkshire Society of Architects.

Suspended from a height, when it rains The Cloud itself rains.

We walked along the valley from the abbey, one of the largest and best-preserved Cistercian monasteries in England. It looked magnificent, with its central tower standing proud among the ruins.

Visitors can access the grounds from the main visitor centre, with its large restaurant and shop, and from the Studley Royal end, where there is a charming tea shop.

It is a wonderful place for children to run around, with wide stretches of grass and woods to explore, plus an imaginatively-designed children’s playground.

There are wild flowers everywhere – we saw bluebells, primroses, violets and wood anemones - adding spring colour to banksides.

On the spot where the 18th century bathing house once stood, fed by natural springs, sits FleaFolly's Listening Tower, a triangular structure containing an echo chamber. Through listening holes - one resembling an ear trumpet - you can hear water dripping. Supposed to spark associations with the lost building, it was more like a tap with a loose washer.

I also wasn’t a fan of Polly, the nine metre-tall tower on Tent Hill, supposedly evocative of an exotic bird.

By internationally-recognised architect Charles Holland, it reminded me of an incinerator, albeit more colourful. My friend called it a ‘broken nail’, while others likened it to pieces of Lego.

A 1770 painting shows a small marquee in the same position, captured from across the valley. From a similar vantage point, Polly, for all its waste disposal unit looks, was quite striking.

We all view art differently, a fact much in evidence on the comment notes in the estate’s Banqueting House, with some visitors being ‘moved and inspired’, while others said the works were ‘not really in keeping’ with their surroundings.

One person summed up my overall feelings: ‘History should be fun and it is here - old and new together.’

It is interesting to see the contrasting works at this National Trust-owned attraction, and look across the valley from one to the other.

The heritage site is also home the only surviving Cistercian corn mill, Elizabethan Fountains Hall with its hidden herb garden and, outside the grounds, St Mary’s Church and a medieval deer park - home to more than 500 wild deer.

*Folly! at Fountains Abbey and Studley Royal runs from April 28 to November 4.

*For more information visit nationaltrust.org.uk/fountains-abbey-and-studley-royal-water-garden and also nationaltrust.org.uk/folly Telephone: 01765 608888