By the early 19th century the fabric of the church had fallen into disrepair.
 All the medieval furnishings were gone, and the interior was as Francis Bumpus later described it, "pewed and galleried to a fearful extent."
Between 1818 and 1830, the tower and choir were restored by George Gwilt Jun. In his efforts to return the church to its thirteenth-century appearance, Gwilt removed the early sixteenth-century windows at the east end of the choir and, lacking firm evidence as to the original design, substituted an elevation of his own invention, with three lancet windows, and a circular one in the gable above.
The transepts were restored, less sympathetically, by Robert Wallace.
The Bishop's Chapel and parochial chapel were removed, but plans for the demolition of the retrochoir were averted, and it was restored by Gwilt in 1832.

At a vestry meeting held in May 1831 it was decided to remove the nave roof, which had become unsafe, leaving the interior open to the weather, and to hold all future services in the choir and transepts.
In 1839, the roofless nave was demolished to within seven feet of the ground, and rebuilt to a design by Henry Rose.

The new nave was at a higher level than the surviving mediaeval eastern part, and closed off from it by a glazed screen.
It had a plaster vault carried on iron columns, and a wooden gallery around three sides.
It was widely criticised, notably by Pugin who wrote "It is bad enough to see such an erection spring up at all, but when a venerable building is demolished to make way for it, the case is quite intolerable."

On the initiative of Anthony Thorold, Bishop of Rochester, the nave was once again rebuilt between 1890 and 1897 by Arthur Blomfield, in a manner intended to recreate its 13th-century predecessor as accurately as possible, and to preserve the few surviving mediaeval fragments.

The main railway viaduct connecting London Bridge station to Blackfriars, Cannon Street and Charing Cross stations passes only eighteen metres from the southeast corner of the cathedral, blocking the view from the south side.
This was a compromise when the railway was extended along this viaduct in 1852; the alternative was to demolish the building completely to allow a more direct passage for the line.
By the early 19th century the fabric of the church had fallen into disrepair.  All the medieval furnishings were gone, and the interior was as Francis Bumpus later described it, "pewed and galleried to a fearful extent." Between 1818 and 1830, the tower and choir were restored by George Gwilt Jun. In his efforts to return the church to its thirteenth-century appearance, Gwilt removed the early sixteenth-century windows at the east end of the choir and, lacking firm evidence as to the original design, substituted an elevation of his own invention, with three lancet windows, and a circular one in the gable above. The transepts were restored, less sympathetically, by Robert Wallace. The Bishop's Chapel and parochial chapel were removed, but plans for the demolition of the retrochoir were averted, and it was restored by Gwilt in 1832.
At a vestry meeting held in May 1831 it was decided to remove the nave roof, which had become unsafe, leaving the interior open to the weather, and to hold all future services in the choir and transepts. In 1839, the roofless nave was demolished to within seven feet of the ground, and rebuilt to a design by Henry Rose.
The new nave was at a higher level than the surviving mediaeval eastern part, and closed off from it by a glazed screen. It had a plaster vault carried on iron columns, and a wooden gallery around three sides. It was widely criticised, notably by Pugin who wrote "It is bad enough to see such an erection spring up at all, but when a venerable building is demolished to make way for it, the case is quite intolerable."
On the initiative of Anthony Thorold, Bishop of Rochester, the nave was once again rebuilt between 1890 and 1897 by Arthur Blomfield, in a manner intended to recreate its 13th-century predecessor as accurately as possible, and to preserve the few surviving mediaeval fragments.
The main railway viaduct connecting London Bridge station to Blackfriars, Cannon Street and Charing Cross stations passes only eighteen metres from the southeast corner of the cathedral, blocking the view from the south side. This was a compromise when the railway was extended along this viaduct in 1852; the alternative was to demolish the building completely to allow a more direct passage for the line.
Southwark Cathedral