Canton Viaduct
Canton Viaduct is a blind arcade cavity wall railroad viaduct built in 1834-35 in Canton, Massachusetts, for the Boston and Providence Railroad (B&P).At its completion, it was the longest (615 feet) and tallest (70 feet) railroad viaduct in the world; today, it is the last surviving viaduct of its kind. It has been in continuous service for 180 years; it now carries high-speed passenger and freight rail service.The Canton Viaduct's walls are similar to the ancient curtain wall of Rhodes (built about 400 BCE) with rusticated stone. It supports a train deck about 60 feet (18 m) above the Canton River, the east branch (tributary) of the Neponset River. The stream pool passes through six semi-circular portals in the viaduct, flowing to a waterfall about 50 feet downstream.The viaduct was the final link built for the B&P's then 41-mile mainline between Boston, Massachusetts; and Providence, Rhode Island. Today, the viaduct serves Amtrak's Northeast Corridor. It sits 0.3 miles (0.5 km) south of Canton Junction, at milepost 213.74, reckoned from Pennsylvania Station in New York City, and at the Massachusetts Bay Transportation Authority's (MBTA) milepost 15.35, reckoned from South Station in Boston.