The City of London

The City of London on Wikipedia.

My knowledge of the divisions of London are very vague. If a church is wrongly listed here, please let me know!

Churches marked † are (in part at least) by Wren. Any corrections would be welcome.
 

All Hallows-by-the-Tower, Barking, Byward Street. TQ 333 806. From an old postcard in Steve Bulman's Collection. A modern view. © Mark Summers. Another view. © Andrew Ross, and another © Peter Morgan. TQ 333 806. Link.
All Hallows, London Wall. © Aidan McRae Thomson. Interior view. © Carole Sarvis. Link.
All Hallows Staining, Mark Lane. Only the tower remains, the rest of the church was demolished in 1870. © Mark Summers. Link.

Bevis Marks Synagogue, on Bevis Marks, is the oldest synagogue in England (1701) and remains in regular use for worship. © Gervase N. E. Charmley. Link.

Chapel Royal of St. Peter ad Vincula (the chapel of the Tower of London). © Peter Morgan. Link.
The ruins of Christ Church Newgate Street† (aka Christ Church Greyfriars) was built on the site of Greyfriars. A Wren church, it was destroyed by WWII bombing. © Gervase N. E. Charmley. Link1. Link2 (for Greyfriars).
Church of the Holy Sepulchre - see St. Sepulchre-without-Newgate below.
City Temple (U.R.C.) on Holborn was originally City Temple Congregational Church (1874) - it was badly damaged in the war. The facade and spire were retained when a new church was built in 1958. TQ 315 815. © Gervase N. E. Charmley. Another view, © Bill Henderson (2014). Link.

Dutch Church, Austin Friars. Interior view. Both © Aidan McRae Thomson.

St. Alban†, Wood Street, a victim of the great fire, and WW2. Only the tower remains. TQ 3235 8146. © Aidan McRae Thomson. Another view, © Christopher Skottowe (1959). An old illustration is available here. Link. Grade II* listed.
St. Andrew-by-the Wardrobe† on Queen Victoria Street was bombed during the war, and has since been re-built. © Gervase N. E. Charmley. Link.
St. Andrew Undershaft. © Mark Summers. Another view. © Gervase N. E. Charmley. Link.
St. Anne & St. Agnes†, Gresham St. Interior view. Both © Aidan McRae Thomson.
St. Augustine†, Watling Street, of which only the tower remains. The medieval church succumbed to the great fire in 1666, and Wrens church to German bombing in 1941. The tower was incorporated into St. Paul's Choir School in the 1960's. TQ 3215 8111. © Aidan McRae Thomson. Another view, © Christopher Skottowe (1959), showing the bombed out church. St. Vedast can be seen in the background. An old illustration is available here, and of its interior here. Grade I listed.

St. Bartholomew-the-Great, Smithfield (Priory Church; open most days, small charge). From an old postcard in Steve Bulman's Collection. A modern view. © Aidan McRae Thomson. Interior view, © Charles Clegg (2012). Link.
St. Bartholomew-the-Less, Smithfield. Interior view. Both © Aidan McRae Thomson. Link.
St. Benet†, Paul's Wharf. Interior view. Both © Aidan McRae Thomson. Link.
St. Botolph, Aldersgate. Interior view. Both © Aidan McRae Thomson.
St. Botolph without Aldgate, on Aldgate High Street. Interior view. Both © John Balaam (2013). Link. Grade I listed.
St. Botolph, Bishopsgate. © Aidan McRae Thomson.
St. Bride† on Fleet Street, undergoing refurbishment. Of Wren's churches, only St. Paul's Cathedral is taller. Consecrated in 1703, it was re-dedicated in 1957, following restoration necessitated by it's having been fire-bombed in WWII. © Gerard Doherty (2013). Link1. Link2.

St. Clement†, Eastcheap. © Aidan McRae Thomson.

St. Dunstan-in-the-East†. Of Wren, only the tower and walls survive, the church having been bombed during WWII. TQ 3316 8072. © Andrew Ross. Another view, © Christopher Skottowe (1959). An old photo is available here. Grade I listed.
St. Dunstan-in-the-West on Fleet Street (Anglican and Romanian Orthodox). Built in 1831, it suffered bomb damage in WWII, and the tower was consequently re-built in 1950. © Gerard Doherty (2013). Link.

St. Edmund, King and Martyr† on Lombard Street. Previously Anglican, now the London Centre for Spirituality. Unusually, this church was damaged by bombing in WWI (according to this link). © Gerard Doherty (2013). Grade I listed.
St. Ethelburga, Bishopsgate. Interior view. Both © Aidan McRae Thomson.
St. Etheldreda Ely (R.C.), Holborn. © Aidan McRae Thomson.

St. Giles, Cripplegate. Interior view. Both © Aidan McRae Thomson. Another view. © Murray Lynn.

St. Helen, Bishopsgate. Interior view. Both © Aidan McRae Thomson. Link.

St. James†, at Garlickhythe. © Mark Summers. Link.
St. Joseph (R.C.). The church is in the basement. © Mark Summers. Link.

St. Katherine Cree (1631) on Leadenhall Street. From an old postcard in Steve Bulman's Collection. The spelling of Katherine varies according to the source consulted, Katharine, Katherine, Catharine, Catherine, though Katherine seems to be most commonly used. A modern view, and an interior view. Both © Gervase N. E. Charmley.

St. Lawrence Jewry†. © Tim Tomlinson. Another view. © David Gallimore. Link.

St. Magnus the Martyr† on Lower Thames Street. © Mark Summers. Another view, and the spire, both © Christopher Skottowe (2015). Link.
St. Margaret Lothbury†. © Mark Summers. Link.
St. Margaret Pattens†. TQ 331 808. © Andrew Ross. Link.
St. Martin's within Ludgate†. © Bill Henderson. Another view. © Aidan McRae Thomson.
St. Mary Abchurch†, on Abchurch Lane, off Cannon Street. Interior view. TQ 3275 8093. Both © Aidan McRae Thomson. A closer view of the tower, © Christopher Skottowe (1959). Link1. Link2. Grade I listed.
The site of St Mary Aldermanbury†, as seen by Streetview in 2019. Another Wren church, another victim of bombing in 1940. The surviving building stone was dismantled and transported to the U.S. in the mid-1960's, where it was re-built at Westminster College, Missouri. It now serves as a memorial to Winston Churchill. An old illustration is available here. TQ 3241 8146. A view of the tower, in situ, © Christopher Skottowe (1959). Link1. Link2.
St. Mary Aldermary†. © Mark Summers. Another view. © Christopher Skottowe (1962). Link.
St. Mary-le-Bow on Cheapside. From an old postcard in Steve Bulman's Collection. A modern view, © Gerard Doherty (2013). Link1. Link2.
St. Mary Somerset, Upper Thames Street. © Mark Summers.
St. Mary Woolnoth (1727) on Lombard Street - a rather bizarre building, designed by Nicholas Hawksmoor. Another view. Both © Gerard Doherty (2013). Link. Grade I listed.
St. Mary's-at-Hill†. TQ 330 807. © Andrew Ross. Link.
St. Michael Cornhill† - in a very cramped location. By Wren (1672), tower by Hawksmoor (1722), restored by Gilbert (1860). © Mark Summers. Link.
St. Michael Paternoster Royal† (1694, restored 1968) on College Hill. Dick Whittington, Lord Mayor of London, was buried here. The church serves as HQ of the Mission to Seafarers. Another view. Both © Gerard Doherty (2013). Link.

The former St. Nicholas Cole Abbey†, now in use as a religious education centre. © Aidan McRae Thomson. Two views (1, 2), both © David Gallimore. Link1. Link2.

St. Olave Jewry, in the City, is one of Wren's churches. It was demolished in 1888, leaving the tower only.  © Simon Kidner.
St. Olave, Hart Street, Aldgate. Samuel Pepys was a regular attendee here. The church was destroyed in the Blitz, but was later re-built. Thanks to Simon Kidner for clearing up my confusion regarding the two St. Olave's. From an old postcard in Steve Bulman's Collection. A modern view. © Mark Summers. Link1. Link2.

St. Paul's Cathedral† (consecrated 1708), from an old postcard in Steve Bulman's Collection. A distant high-level view, showing the cathedral as it's not possible to appreciate it from ground level. © Dave Westrap. Another view. © Aidan McRae Thomson. Another view. © Gerard Doherty (2013). Link1. Link2. Grade I listed.
St. Peter, Cornhill†. © Aidan McRae Thomson. Link.

St. Sepulchre-without-Newgate† (aka Church of the Holy Sepulchre) on Holborn Viaduct. Interior view. TQ 317 814. Both © Aidan McRae Thomson. Another view, © Gervase N. E. Charmley, and another, © Bill Henderson (2014). An old postcard view, (from Paul E. Barnett's Collection) poses a minor mystery. As the photos show, there should be an imposing porch. The card is postmarked 1906, but the porch looks much older. Although I haven't been able to find a precise date for it, Pevsner mentions a re-facing of the stonework of the porch by W. P. Griffiths in 1873-5, so it must be significantly older than this. Link. Grade I listed.
St. Stephen Walbrook†. TQ 326 809. © Andrew Ross. Link1. Link2.

St. Vedast-alias-Foster† (1701, open most days), is near St. Paul's Cathedral. © Bill Henderson. Another view, © Aidan McRae Thomson. Two interior views - 1, 2, both © Charles Clegg (2012). Link.

Temple Church on Inner Temple Lane. On a cramped site, the church is difficult to photograph well. Another view. TQ 312 810. Both © Bill Henderson (2018). Link. Grade I listed.