The following text is from the original listed building designation:
TQ 77 SW HIGHAM CANAL ROAD
3/10005 The Obelisk
II
Boundary marker. Erected in 1820 on the Thames and Medway Canal to mark the jurisdiction of the Cities of London and Rochester for the collection of dues. Granite stone obelisk with inscription and coat of arms, 4 ball finials to the base and plinth with crossed maces and oars. The inscription reads "This boundary stone marking the line of jurisdiction of the cities of Rochester and London on the Medway and Thames Canal was erected AD1820. The Worshipful John Gibbs Mayor of the city of Rochester."
Listing NGR: TQ7045873628

Description from record TQ 77 SW 52:
Obelisk situated on the South side of the Thames and Medway Canal, erected in 1829 to mark the half way point along the canal and the boundary between the cities of London and Rochester, site photographs (1-3).

English Heritage, List of Buildings of Special Architectural or Historic Interest (Map). SKE16160.

<1> 1946, Photograph (Photograph (Print)). SWX9405.

<2> 1946, Photograph (Photograph (Print)). SWX9428.

<3> 1947, Photograph (Photograph (Print)). SWX9833.