The major developments in transportation were that overland transportation was improved by the creation of the National Road, the speed of water transportation was improved by the steamboat that made it easier to travel against the current, new canals provided efficient water transportation that linked farms to expanding cities, and railroads were built which cost less to build, could scale hills easier, moved faster than ships, and carried more weight.
This let people travel further distances for work. Leading to more towns staying stable as if people lived in one location they could take the rivers or railroad to get to the work camps and such. As prior to these developments people had to move where work was located this wasn’t required anymore. As well as this gave thousands of jobs and let jobs be more stable.
