What is the route that has the longest duration? Indicate the city of where the stations are located.
route implies a course taken in getting from start_station_name to end_station_name; the longest duration refers to MAX(duration);
SELECT T1.start_station_name, T1.end_station_name, T2.city FROM trip AS T1 LEFT JOIN station AS T2 ON T2.name = T1.start_station_name WHERE T1.duration = ( SELECT MAX(T1.duration) FROM trip AS T1 LEFT JOIN station AS T2 ON T2.name = T1.start_station_name )