Milestones 1, 2,3 and 4 all appear to be missing. Several trips into this area didn't yield any results. The 4th Milestone would be in the area of Overbrook High School if the route continues along Lancaster Avenue.
Using the West bank of the river as a starting point here are the inns we would have passed during Turnpike days. The Fish Inn sometimes known as the Golden Fish was on the West bank. After that we would pass the Lamb whose exact location has been lost. At about 2 1/2 miles from the river we would pass The Rising Sun and then the Columbus Tavern. The White Lamb was opposite the fourth milestone, near Wynnefield Avenue in 1912, according to Sachse. The Black Horse Inn and Tavern was established in 1720 by the Wynn family. It may have moved to a new location after the turnpike opened in 1794. That new location would be West of City Line Avenue. There is a picture of the Black Horse on the Milestone 5 page. Also found in Lower Merion Township was the Green Tree Inn. A newspaper clipping from the Main Line Chronicle dated Jan. 5, 1956 tells all about that illustrious establishment.
Goggle Map showing portion of the turnpike Miles 1-4. It appears on this map as Lancaster Avenue.
Below: Sketch map of Milestones 1 through 7 of Turnpike