1955 Soo Locks Centennial First Day Cover Block of Stamps

ww FIRST DAY OF ISSUE LAKE STEAMER PASSING THROUGH LOCKS, ONE OF THE BUSIEST WATERWAYS IN THE WORLD. Centennial Art Craft SOO LOCKS CELEBRATING 100 YEARS OF GREAT LAKES TRANSPORTATION 1855-1955 SAULT SAINTE JUN 28 9-AM 1955 MICH 34, SUPERIOR VOIRO SUPERIOR SOO LOCKS-1855 U.S. SAULT SAINTE MARIE -1955 MICHIGAN HURON ONTARIO HURON SOO LOCKS 1855 U.S. SAULT SAINTE MARIE -1955 ONTARIO CENTURY OF A CENTURY OF GREAT LAKES TRANSPORTATION GREAT LAKES TRANSPORTATION -FIRST DAY OF ISSUE 34 ERIE 34 SUPERIOR SUPERIOR SOO LOCKS-1855 U.S. SAULT SAINTE MARIE 1955 MICHIGAN HURON ONTARIO HURON SOO LOCKS-1855 U.S. SAULT SAINTE MARIE 1955 ONTARIO ERIE A CENTURY OF A CENTURY OF GREAT LAKES TRANSPORTATION GREAT LAKES TRANSPORTATION