The 1903 Hamilton Street Bridge looking Southwest. This postcard photo shows three different types of transportation. The Central Railroad of New Jersey tracks cross under the bridge along the east bank of the Lehigh River; the Lehigh Canal and Lehigh River are being used for water transportation in small boats. Also the Hamilton Street bridge facilities road traffic. All of these forms of transportation turned Allentown into a major industrial center as seen by the numerous industrial sites along the west bank of the Lehigh River.