Continue straight ahead up Old Bailey to the Central Criminal Court, better known as the Old Bailey after the street. The building, with its statue of Lady Justice holding sword and scales and its inscription above the door “Defend the children of the poor and punish the wrongdoer”, celebrated its 100th birthday earlier this year. The courtrooms have seen many high profile trials including that of Stephen Ward in the Profumo Affair in 1963.

Cross Holborn Viaduct to Giltspur Street. Halfway up on the left is the Golden Boy of Pye Corner, a memorial to the Great Fire. The plaque underneath the statue records the additional gruesome information that the Fortunes of War pub formerly on the site was where bodies brought by bodysnatchers awaited the attentions of surgeons from neighbouring St Bartholomew’s Hospital.

The handsome buildings of St Barts line the right hand side of Giltspur Street and West Smithfield. This is the oldest hospital in England, founded in 1123 and was the focus of a bitter closure battle in the early 1990s, after which it lost its accident and emergency department.

Follow West Smithfield round to Cloth Fair, a narrow pretty street of houses with overhanging windows and small shop and office fronts. Ahead the concrete towers of the Barbican dominate the skyline. The towers were at first widely criticised for their intrusiveness but now they are popular with homeowners who want to be in the centre of London, City workers and people outside London who want a pied a terre. Turn right into Kinghorn Street and straight on along Bartholomew Close (ignore the turning of the same name to the right). At the end of Bartholomew Close turn left then left again into Little Britain.

Emerge into Aldersgate Street with the Museum of London on your left. This museum is a must for London lovers and you will need several visits to take in everything. The walk route turns right into the small green space of Postman’s Park. This contains a fascinating memorial to ordinary Londoners who died trying to save others like “Frederick Alfred Croft, inspector” who “saved a lunatic woman from suicide at Woolwich Arsenal station but was himself run over by a train June 11 1878”. This is a good place to stop for a rest and a picnic and have a read of the tiled wall of inscriptions at the same time.

From the park, cross Aldersgate Street, named after the City gate of the same name on this site which was demolished in 1761, and turn right, then left into Gresham Street. The church on your left half way up is St Lawrence Jewry, now the Corporation of London’s Church. This church was destroyed in the Great Fire, restored by Wren, only to be almost destroyed again in the Blitz of 1940. A display case inside the door has photographs of the blitzed church and a charred baptismal record book from 1813 which was locked inside a church safe but still burnt because the heat from the firebombs was so intense.

Turn right into the open space outside the 15th century Guildhall, used for City meetings, banquets and receptions and open to the public. Cross the square and turn right into Basinghall Street then right again into Gresham Street. Cross Moorgate to Lothbury. The two copper domes mark the Bank of England, which faces the former Stock Exchange across Bartholomew Lane. The Stock Exchange used to house the trading floor where brokers physically traded stocks – now the Exchange itself has moved to Paternoster Square next to St Paul’s and stocks are traded electronically.

At Threadneedle Street cross and turn left then right into the pedestrianised Royal Exchange buildings, lined with smart shops selling jewellery, bags and designer clothes. At Cornhill, turn left and cross the main Gracechurch Street at the lights.

Bear right for a couple of yards then left into the covered Victorian Leadenhall Market. During the week this is seething with City workers eating, drinking and buying food from the specialist delicatessens but everything is shut at the weekend, although the grade II listed market with its glass canopy is always worth exploring. To continue the walk turn left into Whittington Street and right into Leadenhall Street past the Lloyds of London building. This building, designed by Richard Rogers for the brokers working in the Lloyds reinsurance and shipping markets, caused a stir when it was first built because all the features normally hidden inside, like pipework, ducting and lifts, were on the outside. The building is best at night when it is bathed in dramatic blue light.

Turn left into St Mary Axe and a close up view of the Swiss Re building, popularly known as the Gherkin. Visible from high points on many Times Online walks, the building dwarfs its neighbours both in size and interest. Just before you reach the Gherkin, turn right along the pedestrianised Brown’s Buildings and left into Bury Lane, then right into Bevis Marks. The gates on your right lead to Bevis Marks Synagogue, Britain’s oldest synagogue built in 1701 and open to the public at certain times.

Turn right down Creechurch Lane, left into Mitre Street and left again into Aldgate, then cross at the pedestrian lights to Jewry Street, which curves under the railway bridge and turns into Crutched Friars. Turn left again into Seething Lane past St Olave's church and churchyard, another small oasis of green, then turn left into Pepys Street and right into Savage Gardens to reach Trinity House Gardens. This small park is dominated by a vast memorial to fishing fleets and those in the Merchant Navy who “have no grave but the sea”.

The Tower of London rises up to your left on the bank of the Thames by Tower Bridge. This is deservedly one of London’s biggest tourist attractions but it gets very crowded with long queues during the summer and at weekends. Cross at the pedestrian crossing to the cobbled open space leading down to the river. If you need refreshments here, there are cafes and sandwich bars and you can sit outside admiring the view of Tower Hill and Tower Bridge.

When you are ready, go down to the river and through the gate on your right to reach the Thames Path. For the first time for centuries, you can walk by the river continuously from the Tower of London to London Bridge now that the path along Custom House Quay is complete. Look across the river for views of HMS Belfast and the misshapen egg of City Hall.

Just before London Bridge, follow a sign up to St Magnus the Martyr Church, cross Upper Thames Street and go up Fish Street Hill to Monument and the end of the walk.

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