In this period he travelled across the river to Lambeth, where he lived with Catherine at No 13 Hercules Buildings. (Now replaced by a block of flats.) Lambeth was cheap and also a centre of radical political activity, and a haven for eccentrics and “outsiders”. Here Blake completed some of the most innovative and revolutionary work of the 18th century.

He wove Lambeth into the texture of his poetry, heralded by the line that “there is a grain of sand in Lambeth that Satan cannot find”. London enters his poetry in many different contexts.

In the greatest of his epics, Jerusalem, Blake, carrying the sun as a lamp, travels through London as a pilgrim. The streets of the city are avenues into the spiritual world. That is why the “dark Satanic mills” of Jerusalem can be found in the heart of the capital. They are emblems of eternity, but have a specific and local identity.

While Blake was living in Lambeth, the Albion Mill, on Blackfriars Bridge, was burnt down by arsonists. It was notorious as the first great factory in London. The palm for urban lament, however, must go to the poem from Songs of Experience entitled London: “I wander thro’ each charter’d street, Near where the charter’d Thames does flow. And mark in every face I meet Marks of weakness, marks of woe.”

After Lambeth, Blake was at No 17 South Molton Street. He and his wife rented two rooms on the first floor, just south of where Oxford Street became the Tyburn Road. The apartment is still there, although South Molton Street is now a fashionable appendage to New Bond Street.

His next home, No 3 Fountain Court, lay in a small alley runnning from the Strand to the river, which still exists. It is a blessed place: here Blake died, on August 27, 1827, singing. His last residence in London is in Bunhill Fields graveyard, near Old Street. Blake is buried near Daniel Defoe and John Bunyan. Each week a small bunch of flowers is placed upon his grave.

And did those feet in ancient time...

The 18th-century London of William Blake is not totally lost to us. An astonishing amount remains. And this is especially true around the City, always an area where ancient and modern have rubbed elbows.

Outside Monument Tube station stands the Portland stone Monument, topped with a burst of brilliant gold flame, near the site of the baker’s shop in Pudding Lane where the Great Fire of London started on September 2 1666, destroying 13,200 medieval houses and 89 churches.

Walk up Fish Street; turn right along Eastcheap. Left up Philpot Lane; cross Fenchurch Street and go up Lime Street; left along Beehive Passage.

Old Leadenhall Market on the left is a maze of curved, cobbled streets full of expensive food and gift shops, pubs and chic restaurants. Turn left along Leadenhall Place to Gracechurch Street; right to cross Cornhill; left down Threadneedle Street, London’s financial heart. On the right is the the Bank of England, founded in 1694. Beyond on the left, cross the top of Lombard Street (a banking centre since Norman times), and take second left down Walbrook to St Stephen’s Church, built by Sir Christopher Wren after the Great Fire, with a modern altar by Henry Moore. Turn up Bucklersbury; left along Poultry; right up King Street to Gresham Street. Opposite stands the Guildhall. Here turn right along Gresham Street to its junction with Aldersgate Street. Across on the right is Georgian St Botolph’s Church, with a fine plaster ceiling and stained glass showing John Wesley preaching. From the church, turn right down Aldersgate and New Change to St Paul’s Cathedral.

Walk from its west end along Ludgate Hill, then Fleet Street, to turn right up Hind Court to Gough Square and the house of Dr Samuel Johnson. Back on Fleet Street, cross and go right; past Cock Tavern, left through Temple Bar gateway into a delightful maze of lanes, courtyards and medieval buildings. Crusader effigies lie among marble columns in the 12th-century Temple Church. At No 3 Fountain Court William Blake died. Back on Fleet Street, cross and go left past the Royal Courts of Justice; bear right to cut through their premises (closed outside office hours) to St Clement’s Lane. Cross Portugal Street and continue up St Clement’s; left into Portsmouth Street opposite the tiny Old Curiosity Shop (claiming to be Dickens’s inspiration). At the top of the street is green and tree-studded Lincoln’s Inn Fields. At No. 13 is Sir John Soane’s Museum, cranky, cramped and crammed with treasures. From the northwest corner of Lincoln’s Inn Fields, turn right to Holborn Tube station.

Pubs Ye Olde Cheshire Cheese at 145 Fleet Street (020-7353 6170). What was characterful enough for Dickens, Mark Twain and Arthur Conan Doyle . . .

County City of London.

Distance 4km (2.5 miles).

Typical time Half a day.

Starting point Monument Tube station (Circle and District lines); finish at Holborn (Piccadilly and Central lines).

What to see Monument; Old Leadenhall Market; Bank of England; St Stephen’s Walbrook; Guildhall; St Paul’s Cathedral; Dr Johnson’s House; Temple; Old Curiosity Shop; Sir John Soane’s Museum; Lincoln’s Inn.

What to read Blake by Peter Ackroyd (Vintage).
Christopher Somerville

The Times Walks have proved a huge hit and here are two more you can join:

Windsor Great Park, July 4. Derwent May leads the way.

Aldeburgh, July 18. Richard Morrison walks and talks about Benjamin Britten.

Go to: www.offersinthetimes.com/timeswalks