Biking paths in Boston can be narrow, close to busy roads and devoid of protective barriers. To solve this issue, LivableStreets Alliance is striving to create 200 miles of shared-use “greenway” bike paths in the city by 2030.

Boston Mayor Martin Walsh, a tech-savvy city leader, held a Twitter chat session Friday to interact with college students in the city, including students attending Boston University. The chat, which Walsh...