By the mid-18th century, the whaling industry was in decline and Provincetown had to find a new way to make a living, so it began cultivating tourism. By the 19th century people were traveling either by boat or stagecoach out to Ptown.
In 1848 the first train service linking Boston to Sandwich began, and by 1873 it reached Provincetown. The idea of a canal connecting the bay to the sound had been advanced as early as the 17th century, but it wasn’t until 1914 that a privately built canal was constructed. This private canal wasn’t that much of an improvement: it was narrow and winding, allowed only one-way traffic, and created dangerous currents. In 1928 the federal government bought the canal and the U.S. Army Corps of Engineers rebuilt it. In the 1930s three bridges (two for traffic, and one for the railroad) were constructed. We still use all three.
Provincetown became even more accessible when the Mid-Cape Highway (U.S. 6) was built in the 1950s.