The roads in Boston have no relationship to cow paths, from the 19th century or any other time.
BBF -- Not quite
There are a number of roads in the olde parte of Bostone that relate to since vanished topography
Generally in the 17th and early 18th Century when there were a fair number of cows in town -- people would lead or urge the cows to pasture on the Boston Common --- if there was a hill in the way the path of least resistance was around the hill. Boston in those days had a lot of smallish and 3 major hills so there were plenty of curving paths which eventurally became streets -- curving streets. In a few cases there was sea water to avoid and so the paths went around it.
Then the fun really begins:
1) in a few cases the streets stayed curving as they got wider to accomdate the growing town and later city -- some are still in existence -- High Street, Quaker lane
2) in nearly all cases the hills were removed to fill the harbor to increase the land area of the town and later city -- Pemberton Hill was leveled but -- Pemberton Square remains
3) in some cases the streets were straightened as they were widened -- buildings were moved
4) in some cases buildings were built with curvature to accomodate the curve in the street the hill having vanished -- the Bulfinch Tontine Crecenst being one of the most notable -- but long since gone -- the Sears Crecent now located on City Hall Plaza is the most relevant where a curving street still exists although the curve is new
5) Most of the buildings were torn down when the streets were widened -- in a few cases the curved buiding remains though the street was widened and straightened -- Kilby St & Liberty Square
6) in a few cases new curves were introduced to connect old streets for new developments such as Government Center and the Charles River Park
Other stage bits of topography involved water that was later filled or mudflat later filled -- these are now mostly manifested in strange names:
1) Dock Square -- formerly the location of the 'Town Dock"
2) Canal Street -- there was a canal
3) Causeway Street -- there was a causeway
4) Fort Point Channel - relates to an old fort attop hill sitting on the harbor -- fort, hill and point are now long since restructured only a small bit of the harbor -- Fort Point channel sill comes close to the original location
The exercise is left to the reader & the pedestrian to find others -- its kind of fun