The plaque marking the work spelled Chafee with an extra "f," as the governor noted.
Officials say the Cliff Walk is Rhode Island's most heavily-visited tourist attraction.
"I can't think of anyplace else along the East Coast where you can have spectacular views, fresh air and beautiful mansions on your other side as you walk down," said Senate President Teresa Paiva Weed, who walked the path with Chafee and Newport Mayor Harry Winthrop.
Newport, one of the oldest seaports in the United States, became a popular summer resort for the rich in the 19th century, starting with Southern planters who wanted to get away from the heat in their home states.
While the houses that summer residents built were often called cottages, they were substantial mansions like the 70-room The Breakers, built by the Vanderbilts in the 1890s, and Kingscote, a Gothic Revival building originally owned by George Noble Jones, a Southern planter who began it in 1839.