Richard Long: Earth Sky, Houghton Hall

“I’m a great opportunist,” says Richard Long, a statement that for all its economy brims with contradictions and possibilities. While his sculptures made in wild and far-flung places often look stumbled-upon, incidental, his method is so careful and considered, each gesture so meticulously planned, that opportunism seems hardly the word for it.

Even so, it was evidently with almost schoolboyish relish that he seized the chance to work on a grand scale at the Norfolk estate of Houghton Hall, home of David Cholmondeley, 7th Marquess of Cholmondeley.

His six new works take their place in Houghton’s burgeoning sculpture park, which already features one permanent work by Long from 2003, and pieces by artists including James Turrell, Rachel Whiteread and Anya Gallaccio. It is Long’s biggest exhibition since his Tate retrospective in 2009, and a unique and unprecedented opportunity to experience a group of his outdoor works together.One of the country’s finest examples of Palladian architecture, Houghton Hall was built by Britain’s first Prime Minister Sir Robert Walpole. Set in parkland shaped by classical ideals of line and balance, tempered by a very 18^th-century English understanding of the picturesque, it is an embodiment of not just English sensibility but history. Long’s sculptures, made from the stone and wood of England, are very much of this place, although they are not always entirely in harmony with it. The Houghton Cross (pictured above) erupts, its fiercely jagged slates cutting through the immaculate surface of the croquet lawn. It is the contrast between primeval matter, and the impossibly smooth lawn and hedges that surround it, that gives it its raw force.

The Houghton Line (pictured below) is more nuanced: a line formed of piles of the local Carr stone, an orange-brown material heaped up like an excavation, should surely appear like a wound in the landscape, gouged into the perfect green of the lawn. Instead, bisecting the centre of the house, there is an unexpected symmetry to it, and it seems more like a manifestation of some mystical alignment. In the immaculately designed grounds of Houghton Hall, it is as if centuries of cultivation have been stripped back to expose something elemental beneath.

If the Houghton Line seems to echo with the memory of some ancient leyline or track, it also relates to the walks for which Long has become perhaps best known. The line was paced out by Long, and its very existence and the decisions about its precise situation were borne out of the artist’s walks around Houghton, which he first visited 14 years ago. For the viewer too, the act of walking from piece to piece is intrinsic to the experience, with each sculpture changing as you walk around it, towards it, and away from it.White Water Falls of china clay appear and then disappear behind an arcade, while Full Moon Circle (main picture), slick with rain, looks from a distance like a pool of water, a silvery slash in the grass. As you get closer the piece ripples silver and dark, the slates overlapping like irregular fish scales that undulate as they catch the light. In sunlight, I am told, it changes, and in the moonlight, is different again.

First made in 2003, but now relocated to this central point at Houghton, Full Moon Circle has a clear affinity with the follies that once were plentiful here. Fulfilling a traditional purpose to delight and surprise, Full Moon Circle is both an intrusion into the landscape and at one with it. Of all Long’s works at Houghton, the most exquisite example of this strange tension is found in his circle of upturned tree roots, simultaneously a harmonious rearrangement of natural features in the landscape, and an outrageous perversion of natural order. The trees, apparently rooted in the air, seem to grow downwards into the ground. And yet as remains of trees that fell long ago, on this very ground, White Deer Circle blends unproblematically into the landscape, the deer wearing them down and gradually destroying them by using them as scratching posts.

Like Long’s other sculptures here, there is a sense of some cosmic significance invoked, their henge-like appearance combining with their position on the site of the old village of Houghton to create an eery sense of place. Standing here, on a rainy cold April day, the wonderful vistas of Houghton dissolving into a misty horizon, with no traffic, no passing aircraft and no mobile phone signal, one stands on the edge of the world, as if at the point where earth meets sky.

• Richard Long: Earth Sky at Houghton Hall, Norfolk until 26 October 2017
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