Graywolf wrote:
> Oh, there is a system.
[...]
> Interstates with odd
> 100's (I-375) are spurs that do not connect back to the original, with even
> 100's (I-485) they are bypasses or through routes that reconnect with the
> main Interstate.
Sort of. I270 does not connect back to I70; it bridges I70 and I495.
The mnemonic I learned, which isn't bulletproof but seems to work
pretty well in the Mid-Atlantic states at least, is:
TWOxx "goes TO xx" and is thus a spur,
THREExx "goes THROUGH town",
FOURxx "is an alternative FOR xx" and is a beltway or bypass.
Beltways I run into tend to be 4xx, 6xx, 8xx (if you've already
used I495 to go around Washington, you use I695 and I895 to go
around Baltimore. Boston is far enough away to use I495 again
without confusion. But interestingly both Baltimore and Washington
have an I395 going into town (perhaps because the Washington one
starts in Virginia?).
1xx does seem to be a spur that doesn't connect back, fitting the
pattern you described. I'm trying to remember where I've seen
5xx -- I know I have, but don't remember where.
What you describe may be more official than what I've laid out,
and my pattern may reflect a few local exceptions or borderline
cases; I don't know.
> State, county, and local routes may do anything. Many seem to have no rhyme
> nor reason in their labeling.
Some _don't_ have rhyme or reason; some states do have a pattern
which may or may not make sense without having it explained.
> Historically, prior to the number system US highways were named. The Lincoln
> Highway was the first. That only started in 1926. Before that I guess you
> had to ask a local for directions.
Most of 'em are still named, aren't they? Though the numbers are
so convenient that a lot of people never say or hear the names and
therefore forget that the names are there. Once in a while there'll
be a naming or a name change to honour somebody or other. And I do
hear people (hmm ... mostly age 50+, come to think of it) giving
directions using highways' names instead of route numbers. Occasionally
I've seen someone have to stop and think a while to remember the
number when a younger person asks, "Which route number is that?"
I used to commute on the John Hanson Highway every day. In my
senior year of high school I had a choice of that or Defense
Highway to get to school. I meet a friend for shopping by taking
Gov. Ritchie Highway. When heading to Greenbelt, my quickest
route is the Gladys Noon Spellman Parkway. Crain Highway takes
me to my mother's house. Traffic reports in Baltimore tell me
about conditions on the Jones Falls Expressway (often abbreviated
"JFX"). If I want to head towards Philadelphia, I'll hit the
John F. Kennedy Memorial Highway. When I spent a lot more time
cutting through DC to get to Virginia, I had many close calls
on Shirley Highway. I'm young enough to think of most of these
by number instead of name, but I recognize the names and am used
to hearing them often, including on the radio.
Admittedly names<->numbers is not a one-to-one correlation.
A route can stay a single road but change names when it
crosses a county line or something, and a route can designate
a path that traverses several different roads. US1, for example,
comes into Baltimore on Wilkens Avenue, but it turns north on
Fulton Avenue while Wilkens continues on (southbound US1 at
that point is Monroe Street). When Fulton crosses North Avenue,
Fulton keeps going but US1 turns east on North. It finally
escapes Baltimore on Belair Road.
More US Highways than Interstates seem to be named, but there
are a couple of Interstates among the examples I gave.
Damn, I spend way too much time thinking about things like
this.
-- Glenn
