The engineering of the Morden extension of the C&SLR from Clapham Common to Morden was more demanding, running in tunnels to a point just north of Morden station, which was constructed in a cutting.
Udførelsen af Morden-forlængelsen af C&SLR fra Clapham Common til Morden var mere krævende, med forløb i tunneler indtil et punkt lige nord for Morden Station, der blev anlagt i afgravning.