Context: The New Haven Division buses follow routes that had originally been covered by trolley service. Horse-drawn steetcars began operating in New Haven in the 1860s, and by the mid-1890s all the lines had become electric. In the 1920s and 1930s, some of the trolley lines began to be replaced by bus lines, with the last trolley route converted to bus in 1948. The City of New Haven is in the very early stages of considering the restoration of streetcar (light-rail) service, which has been absent since the postwar period.

Question: What form of public transportation preceded the current New Haven Division bus routes?
Answer: trolley service

Question: What decade ushered in the operation of horse-drawn carriages in New Haven? 
Answer: the 1860s

Question: What advancement was made to New Haven trolley lines in the mid 1890's?
Answer: all the lines had become electric

Question: What mode of public transportation in New Haven phased out the trolley service in the 1920's and 1930's?
Answer: bus lines

Question: In what year was the final trolley route in New Haven converted to a bus line? 
Answer: 1948

Question: Buses in New Haven uses what kind of route for their service?
Answer: trolley

Question: Before 20th century, what was the form of public transportation in the city?
Answer: Horse-drawn steetcars

Question: In what year were trolleys finally replaced completely by buses?
Answer: 1948

Question: What further ideas for public transportation is the city currently considering?
Answer: streetcar (light-rail) service