[QUOTE=GorillaMan]
I’m pretty sure we’re talking about the same section of road (east-west, just south of the airport?) If I’m wrong I apologise, but it looks to me like paired 3/4/5 lane highways, with a shoulder & median separating them, not a nine-lane free-for-all. If this isn’t what it’s like on the ground, then what is it?
[/QUOTE]
You’re pretty correct for most of the 401 through Toronto. The only part not like this in the Metro area is what we used to call “the Martin Grove bottleneck,” which is just east of the airport. It’s indeed a free-for-all.
Anyway, it may be confusing to those who haven’t seen or driven it before. Essentially, the 401 is like the New York subway: there are express lanes, in the middle; and collector lanes, on the sides. Just as the express and local trains make up the subway, so do Express and Collectors make up the 401. Collectors often handle local traffic–those cars going one or two or three exits, say–while Express handles cars going farther; or indeed, just through the Greater Toronto Area. But note that regardless of how far you’re going or what set of lanes you want to travel in, you will always enter and exit the freeway from Collectors.
The express/local analogy is the theory. In practice, it differs. You can, if you like, get all the way across the GTA in Collectors; or you can get on Collectors, get over into Express, and exit Express to collectors at the first (or second or third or whatever) opportunity. This is sometimes necessary if you expect to get anywhere–an accident in Collectors that forces Collectors to come to a complete halt does not stop Express (though it often slows it down as people slow to look). And vice-versa.
To Torontonians and others who have, shall we say, experienced the 401 through the GTA, there is no difference–in other words, the 401 is not “the lanes in the middle,” and neither is Collectors just on- and off-ramps The speed limit is the same for Express and Collectors, highway markers identifying the highway as 401 are in Collectors, and you can get through the GTA in Collectors. Looked at this way, the 401 is just as wide as other posters have said: adding Express and Collectors eastbound and Express and Collectors westbound, you get something like 16 or 18 lanes wide at its widest.
Spoons
(who drove the 401 across the GTA daily on his way to work when he lived in Toronto)