Country diary: the way through the woods leads to a mysterious grotto | Environment

Our footsteps are quieted by fallen leaves as we enter Hartburn Glebe, a curve of ancient semi-natural woodland hugging the steep sides of the Hart Burn. There is something of Kipling’s poem The Way Through the Woods about it, a past glimpsed beneath the undergrowth. There was “once a road through the wood”. The Devil’s Causeway, a Roman road that ran north-east to the Tweed, passed through here, seen now as a holloway under woodrush and conifers.

Wide steps, half hidden by beech leaves, descend towards the river. A stone footbridge, with no parapet, stretches across a deep cleft, its side pierced by an elegant lancet arch through which tumbles a small stream. The late afternoon sun patterns the tree trunks with the heart-shaped shadows of ivy.

4000 - Country diary: the way through the woods leads to a mysterious grotto | Environment

Interior of the Hartburn Grotto. Photograph: Alamy

The path drops to the river where mounds of brown-tinged foam remain wedged against the bankside; the river was in spate a couple of days ago. A slender waterfall plummets between sandstone bluffs to join frothing rapids. The wildflowers that indicate the age of this wood lie dormant for now: wood anemone, lords and ladies, bugle, wood sorrel. In spring, the air will be pungent with the scent of wild garlic and sweetened by bluebells.

As we walk upstream, the burn levels out into calm pools. To our left rears a cliff, its surface silvered by lichen, ferns and woodrush drooping from its ledges. Carved into it is a tall narrow entrance and, above that, a pair of roundheaded niches, believed to once hold statues of Adam and Eve. Looking up, the effect is of a grotesque mask. Perhaps the entrance was high to let out smoke, for inside there is a circular chamber with a fireplace, and a further room through a gothic archway. Someone has left votive candles on the rocky shelves and two faded blue plastic chairs.

Known as Hartburn Grotto, this grade II-listed structure was created from a natural cave in 1760 by Dr John Sharpe, the vicar who landscaped these woods. It was designed as a changing room for bathers, with a slab-roofed tunnel for discreet access to the water. On this December day, with the light dropping, the water looks numbingly cold.

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