“The Irish border, that invisible line that cuts this island in two,” Kerri ní Dochartaigh writes in her literary debut, “has been around for a single century”. For some 20 years now the volatile land surrounding the border has known relative peace. But at the time of her writing this memoir, in 2019, the ramifications of Brexit have stirred old tensions. Bombs have begun to explode again. Public and personal tragedy blurs. The news of journalist Lyra McKee’s shooting by dissident Republicans in her hometown reaches the author as she learns of her best friend’s suicide.

Ní Dochartaigh was born in 1983 at the exact midpoint of the Troubles in Derry-Londonderry — where the “conflict is widely accepted to have started” — to a Catholic mother and Protestant father. Having been forced out of a Protestant council estate by a petrol bomb thrown into her room, then driven out of the Catholic estate to which her family was reassigned, she has carried with her a feeling of not belonging.

After an early adulthood spent moving around the British Isles Ní Dochartaigh was drawn back to Derry in her thirties, and to spots she first explored with her grandfather. “The places he spoke of were locations where people felt very different from how they normally do. Places from which people came away changed.” Thin Places catalogues these, and the emotional resonance they hold for the author, both on the island of Ireland and further afield.

The Celtic people, Ní Dochartaigh tells us, incorporated a “Fifth Province” into the geography of ancient Ireland: “the magical ‘Otherworld’” between physical and spiritual realms. Twentieth-century geopolitics bears out equivalent anomalies. The Lough Foyle, an estuary between counties Derry and Donegal on either side of the border, belongs to neither the North nor the Republic. Yet it was called “the borrowed lough” even in folk tales from hundreds of years ago.

This book, too, is one of those multifarious non-fictions that do well at the moment; mixing memoir, nature writing and cultural history in one unified narrative.

Grief and trauma have followed Ní Dochartaigh. She movingly addresses the murder of a childhood friend in a rural hamlet, and a period in her twenties in Cork when she attempted suicide four times. A moment in which she briefly transcended grief on a black shore in Iceland, following the death of her grandfather, is rendered particularly luminous. States of acceptance and even solace are attained by the author, though the gravity of the book’s tone is unremitting.

“Nature is not always silent and a bringer of healing”, we are told. Quite right. There is something dispiriting about the current narrative in nature writing that casts wild space as a simple source of replenishment to the urban human, addled by life and society and the past.

The strength of Ní Dochartaigh’s vision is that nature doesn’t have to be uncomplicatedly lovely. Her thin places are ancient burial sites, but also fields at the back of an estate or a built-up back garden with a cherry blossom tree in it. Her book “[seeks] beauty in the murk” as well as in the obviously picturesque.

Yet Thin Places never really offers a convincing alternative. The ambivalence and “otherness” of the project is contradicted by a familiar language of breakdown, recovery and consolation: “the lines of my map had blurred and I didn’t have a compass”; “Grief is a country that has no definite borderlines”. Nature too readily offers up its hoard of metaphors. A starker rhetoric might be better suited to the in-between places Ní Dochartaigh evokes. One not yet owned on either side of the border between self-help and nature writing: one that doesn’t yet belong.

Thin Places by Kerri ní Dochartaigh, Canongate RRP£14.99, 272 pages

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