The Grey Horse Inn, 86 High Street, Stockton included in a general view of the south end of the High Street. c1795 
Picture Stockton Archive
A Pictorial History of Stockton-on-Tees
The Grey Horse Inn, 86 High Street, Stockton included in a general view of the south end of the High Street. c1795
The very old print showing the Stockton High Street certainly does show what appears to be Castlegate on the right and Yarm Lane on the left. Incidentally about the time of this old print, the map of Stockton in 1825 shows Yarm Lane with at Timber yard on the left side before you get to Holy Trinity grounds. Alson Bishopton Lane at that time was called “Brown bridge Road”
Looking at this old print of the High Street long ago I supect that the two openings on the extreme left and right in the foreground are YarmLane and Castegate. Does anyone think also?