Part 10/14:
In the 1910s and 1920s, expansion projects like the 1914 extension to Kenmore Square and the 1932 incorporation of surface streetcar loops into underground tunnels signaled ongoing efforts to modernize. However, these changes, along with urban reforms aimed at wider streets and new traffic patterns, gradually rendered many original portals and tunnels redundant or obsolete.
The rise of automobiles in the 1920s and 1930s heralded a new era. Policymakers prioritized highways and parking over rail infrastructure, diverting funds away from streetcar systems. The introduction of the Huntington Avenue Subway in 1949—Boston’s second subway line—further diminished streetcar routes, as many tunnels and portals like the Boilston Street portal were closed or sealed.