“Walking in a place in which you feel rooted is deeply restorative. I favour the deep country, ideally not encountering another person for hours. The natural world is astonishing. Every time you walk the same walk, you see or hear something new. Nature halts self-absorption, makes you less frantic about all that’s going on in your own small mental or physical world.

“Performers are expected to maintain their looks as they grow old, but not writers. We can become eccentric and nobody minds, which is a great freedom. Face on in the mirror, I think I look fine. I don’t like it at all, though, when I catch sight of myself by surprise in a shop window and from the side. Even so, I’d never dream of surgery, to take any risks that aren’t strictly medical. Better to learn to like yourself as you are. And, again, walking in the country helps. No mirrors, no reflecting windows, and you return home fitter and looking better than when you set out.

“You must stay true to your beliefs. At 99, you’re probably not following even the world’s greatest outrages as closely as you did when you were my age, but for now I am as upset as ever by certain issues, so I speak out. What I have lost interest in is Westminster politics. I’ve a sense of looking at it from a greater distance than I used to. These days, I tailor my energies to things that are really important, and Peter Mandelson isn’t one of them.”

The pearl: “If you can’t get out and walk, do something indoors that will take you out of yourself and keep melancholy at bay. For some it’s chess or knitting or embroidery. For me it’s always been a good jigsaw.”

Dame Margaret’s anthology, A Writer’s Britain, is published by Thames & Hudson, price £12.95

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