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A line of roads or tracks known as the 'Salt Way' (or 'Saltway', 'Salter's Way') can be traced for about 40 miles across the north-east part of Leicestershire into Lincolnshire. The identifiable route (who knows its western and eastern limits?) essentially corresponds with Roman roads, Margary numbers RR58a and RR58b. (Ref. 'Roman Roads in Britain', Vol. 1, by Ivan D. Margary).
RR58a started at the River Soar (Barrow upon Soar); crossed the Fosse Way (RR5f, modern A46) at Six Hills; ran along the Belvoir escarpment and Leicestershire Wolds; crossed the River Witham at Saltersford (SK 927 334), which may be the site of the Roman settlement of 'Causennae'; before joining Ermine Street (RR2c, modern B6403) near Cold Harbour.
From Ermine Steet RR58b, also known as 'Salt Way' ran along, or close to the line of the modern A52 into the Fens at Donington. Fuller details and references at Link

A 57-mile man made ancient drainage watercourse between Lincoln and Peterborough. The circumstantial evidence points to the skill of Roman engineers but documentary evidence is inconclusive, though it is generally assumed to be Roman.
It was originally thought to continue south of Peterborough to the Waterbeach canal, north east of Cambridge, but no link has been proven.