Most people would like a larger wine cellar. Few go to the same lengths as William Lyttle, who began excavating his basement 40 years ago and didn’t know when to stop. Beneath his house in Hackney, London, he has scooped out a labyrinth of tunnels that extends in all directions, cracking pavements, weakening foundations and seriously alarming neighbours, the council and structural engineers.

Like Swampy, the Mole Man is at a loss to explain his troglodytic instincts. But humans have been obsessed by burrowing, in peacetime as in war. The warren of Hezbollah dugouts, undermining much of southern Lebanon, is in a long tradition of military tunnelling: Gibraltar and the white cliffs of Dover are honeycombed with secret passages. London Underground workers were conscripted to dig deadly tunnels under enemy lines in 1916 to detonate mines under the trenches; in the Second World War naval codes were deciphered deep in tunnels as PoWs in Germany were vaulting wooden horses and tunnelling to freedom.

Mao became obsessive. “Dig tunnels deep! Store grain everywhere!” were his gnomic commands. He left a cavernous legacy under Beijing, 20 miles long, of air-raid shelters that now house factories, mushroom farms and even hostels for impecunious tourists.

No tunneller can match William Cavendish-Scott-Bentinck, the reclusive 19th-century 5th Duke of Portland. For 25 years he employed 1,500 men under the grounds of Welbeck Abbey, digging out a library, billiard room, ballroom and gas-lit tunnels wide enough for two carriages. They were never used or explained. Like Mr Lyttle, he simply enjoyed tunnelling.