Which is the worst T route right now?

Problems continue to dog the T—did you hear the one about inbound Orange Line riders going outbound to find less-crowded trains?—and no other season accentuates such challenges more than winter, with its blustery precipitation and chilly temps.

So our latest open thread is a simple one: Which is the worst T route in terms of delays, crowds, general misery, etc?

It can be a trolley line, a subway or a bus route, or a commuter rail run. Share not only the what, but the why: Why do you think the route is so chronically awful? The infrastructure? The new development along it adding that many more passengers?

And, if you care to share any hacks about making it more tolerable, do that, too, in the comments section below—though we understand if you might want to keep such workarounds to yourself.

• The Orange Line is so crowded, some passengers go out to get in [Globe]
• Boston transportation projects that need to hurry up and arrive [Curbed Boston]
• Red Line stations’ major construction—the big projects, mapped [Curbed Boston]
• Blue Line development: Lots of construction along the Boston-Revere route [Curbed Boston]