Inter-modal Network Externalities and Transport Development: Evidence from Roads, Canals, and Ports during the English Industrial Revolution

How does the development of one transport mode influence the development of another? This paper uses time-series data to test whether inter-model network externalities influenced the development of road, canal, and port infrastructure in England from 1760 to 1830. The main finding is that road development had a positive effect on canal development. The results suggest that the option value of investing in a canal in the future diminished when nearby road improvements were initiated because there was less uncertainty about future profits from canal tolls. They also suggest a reinterpretation of road transport in the Industrial Revolution and point to the general importance of inter-modal network externalities.