At 21 m. a tablet marks the site of the Parmenter Garrison House, built before 1686. The carpenters building the Wayside Inn (L) took refuge here during an Indian attack.
At 21.1 m. is a junction with the Old Boston Post Rd., again an alternate to US 20.
Right on this road .3 m. is the Wayside Inn (guide; adm. 25 cents), the core of which was built by Samuel Howe in 1686 and immortalized by Longfellow in "Tales of a Wayside Inn." It is now owned by Henry Ford, who added a two story wing and restored some of the original appearance... When the Inn was first opened to the public, it was known as Howe Tavern, but after 1746, when Col. Ezekial Howe put up a new sign, it became known as the Red Horse Tavern...
At 0.4 m. on the Post Rd. is the Redstone Schoolhouse, a small red frame building set in a grove of pines. A tablet on a huge boulder near it says that the old school house is the one immortalized in "Mary Had a Little Lamb." This claim, however, is disputed.
Between Sudbury and Marlborough US 20 passes through a pleasant countryside, predominantly orchard land.