Not all subway lines are created equal. In fact, some lines run like clockwork, while other trains are plagued by filth and grime, long waits and overcrowding.


The 7 and the L were deemed the best lines, according to a study released today by the Straphangers Campaign. But the C line is by far the worst in the system, finds the report, which used MTA data to rank the lines.


The 7 made the top of the list because of its clean cars, availability of seats, infrequent breakdowns and frequency of service. The 7 train comes an average of every 2-and-a-half minutes during the morning rush, compared to a systemwide average of a 5-and-a-half-minute wait on other trains.


Riders on the C, however, endure long waits for trains, a higher frequency of mechanical breakdowns and dirty trains.


C-train riders agree with the report's findings.

"Living on the C line is definitely not the best," said Ilana Arazie, 35, disembarking from a C at Port Authority this afternoon. "It's slow and it doesn't show up very often."