The Henley Bridge Monument was built in 1939 by William Lyon Somerville and is historically significant, not just for its design and craftsmanship, but its importance in inaugurating the first visit to Canada by the Queen Mother of Elizabeth II. The Queen Elizabeth Way (QEW) was the first intercity divided highway in North America and featured the longest stretch of consistent illumination in the world.

The main components of the Queenston limestone monument are designed to resemble the bow and stern of a Roman galley (possibly a Trireme). The eastern end of the monument represents the stern and the western end the bow. The entirety of the monument is embellished with provincial crests, heraldic figures and the Royal Coats-of-Arms.

Innovative Civil Constructors Inc., (ICCI), was retained in 2017 by the Ministry of Transportation (MTO) to perform repairs on the Henley Bridge. Conservation treatment and monitoring were required on the two east and west-end Henley Bridge monuments. Spencer Higgins Architect (SHA) was retained by ICCI in April 2018 to act as a heritage consultant and provide project oversight. ArconTEST Incorporated assisted SHA in documenting all phases of masonry work and an initial assessment of the conservation treatments.

ArconTEST Incorporated was subsequently retained by ICCI to conduct a sequence of ten condition assessments of the Henley Bridge Monument during their work to repair the bridge. The recommended minimal conservation treatments were completed in mid June 2019. SHA recommended to MTO that full rebuilding of both monument piers on new elevated podia and full conservation of the Queenston limestone sculptures be carried out in the near future.

Measured as-found drawings and specifications detailing materials and methods of repair for the Henley Bridge Monument were created by SHA. All repairs and their corresponding locations were documented on the record drawings.