AARoads Forum

National Boards => General Highway Talk => Topic started by: Alex on July 09, 2009, 11:46:24 AM

Title: How many Interstate Exits are there?
Post by: Alex on July 09, 2009, 11:46:24 AM
Does anyone have a rough idea of how many exits there are on the entire Interstate system sans Hawaii?

There are 20 exits in Delaware:
I-295 - 2
I-495 - 6 (including DE 92's off-ramp)
I-95 - 1, 3, 4, 5AB, (5C), (5D), 6, 7, 8, 9, 10, 11
Title: Re: How many Interstate Exits are there?
Post by: mightyace on July 09, 2009, 11:50:34 AM
Quote from: AARoads on July 09, 2009, 11:46:24 AM
Does anyone have a rough idea of how many exits there are on the entire Interstate system sans Hawaii?

There are 20 exits in Delaware:
I-295 - 2
I-495 - 6 (including DE 92's off-ramp)
I-95 - 1, 3, 4, 5AB, (5C), (5D), 6, 7, 8, 9, 10, 11

Doe the figure for I-295 include the Lander's Lane ramp?

EDIT:
P.S. I remembered that because we'd take often take that ramp as a back way to the neighborhood where my paternal grandfather lived.

He was a school superintendent and there has been an elementary school named after him for over 30 years.
http://www.colonial.k12.de.us/harryeisenberg.shtml (http://www.colonial.k12.de.us/harryeisenberg.shtml)
Title: Re: How many Interstate Exits are there?
Post by: Alex on July 09, 2009, 11:53:13 AM
Quote from: mightyace on July 09, 2009, 11:50:34 AM
Quote from: AARoads on July 09, 2009, 11:46:24 AM
Does anyone have a rough idea of how many exits there are on the entire Interstate system sans Hawaii?

There are 20 exits in Delaware:

I-295 - 2
I-495 - 6 (including DE 92's off-ramp)
I-95 - 1, 3, 4, 5AB, (5C), (5D), 6, 7, 8, 9, 10, 11

Doe the figure for I-295 include the Lander's Lane ramp?

You know what, it does not, so that can be bumped up to 21.
Title: Re: How many Interstate Exits are there?
Post by: akotchi on July 09, 2009, 12:00:40 PM
Gee . . . go ahead, pick a small state, why don't you.   :-P

I presume by your count that you mean interchanges, so that a cloverleaf counts as only one exit, even though it has two exit ramps.

And for those of you scurrying to count the exits for your state, Interstate-to-Interstate interchanges only count once!
Title: Re: How many Interstate Exits are there?
Post by: Alex on July 09, 2009, 12:07:06 PM
Quote from: akotchi on July 09, 2009, 12:00:40 PM
Gee . . . go ahead, pick a small state, why don't you.   :-P

I presume by your count that you mean interchanges, so that a cloverleaf counts as only one exit, even though it has two exit ramps.

And for those of you scurrying to count the exits for your state, Interstate-to-Interstate interchanges only count once!

I was discussing this with a colleague and he was thinking that half-exits (like westbound off-ramp eastbound on-ramp) would count as one exit (unless they are in a split-diamond configuration). Cloverleaf interchanges should only count as one exit.

Not looking for anything super precise, but in the Landers Lane case the off-ramp is only accessible via eastbound and not associated with U.S. 13/40 or Delaware 9's interchanges, so it gets to count as an exit (thanks MightyAce!). I suppose the 30 or 40 at-grade intersections in west Texas on Interstate 10 could count as independent exits too.

I just randomly threw Delaware out there because its the one state where I know and have taken every exit.  :colorful:
Title: Re: How many Interstate Exits are there?
Post by: 74/171FAN on July 09, 2009, 01:30:14 PM
For the I-x95s in Virginia(including VA 895):
I-95-73(4,8,11A-B,12,13,17,20,24,31,33,37,41,45,46,47,48A-B,50A,50B-C,50D,51,52,53,54,58A-B,61A-B,62,64,67A-B,69,73,74A,74B,74C,75,76A,76B,78,79,80,81,82,83A-B,84A-B,86A-B,89,92A-B,98,104,110,118,126A-B,130A-B,133A-B,136,140,143A-B,148,150A-B,152A-B,156,158A-B,160A-B,161,163,166A-B,167,169A-B,170A-B,173,174,176A-B,177A-B,177C)(does not include HOV exit at SR 7900/Franconia-Springfield Pkwy)
I-295-19(1,3A-B,9A-B,15A-B,22A-B,25,28(counts as 2 for US 60 and I-64 I think), 31A-B,34A-B,37A-B,38A-B,41A-B,43A-B,43C-D,45A-B,49A-D,51A-D,53A-B)
I-395-12(1A+C-D,1B,2A-B,3A-B,4,6,7A-B,8A-B,8C,9,10A,10B-C)
I-495-10(43,44,45A-B,47A-B,49A-B,50A-B,51,52A-B,54A-B,57A-B)
VA 895-3(I-95,VA 5,I-295)
Overall:117
not including VA 895:114
Title: Re: How many Interstate Exits are there?
Post by: mightyace on July 09, 2009, 05:02:16 PM
Would I be correct to assume:

1) Toll Barriers at the end of ticket systems do not count, even though the toll roads (i.e. PA Turnpike, NYS Thruway, Ohio Turnpike, Indiana Toll Road, etc.) count them as such.

2) Also, that exits that aren't "for everyone" still count.  i.e. The so-call "slip ramp" EZPass-only exits on the PA Turnpike, exits on HOV lanes that don't match up with a non-HOV exit.

3) Ramps between "dual carriageways" (i.e. Express-Local lanes) do not count.
Title: Re: How many Interstate Exits are there?
Post by: agentsteel53 on July 09, 2009, 05:07:24 PM
Quote from: mightyace on July 09, 2009, 11:50:34 AM
the Lander's Lane ramp?

I just looked that up!  WTF is that thing??  There is no return to the freeway, nor is there a corresponding exit on the westbound lanes.  Did someone just build that exit to his own house when no one was looking??
Title: Re: How many Interstate Exits are there?
Post by: mightyace on July 09, 2009, 05:19:17 PM
Quote from: agentsteel53 on July 09, 2009, 05:07:24 PM
Quote from: mightyace on July 09, 2009, 11:50:34 AM
the Lander's Lane ramp?


I just looked that up!  WTF is that thing??  There is no return to the freeway, nor is there a corresponding exit on the westbound lanes.  Did someone just build that exit to his own house when no one was looking??

I don't know the story behind it but it seems have been there since the freeway opened.  I remember taking it as a kid and going from this multilane freeway and being dumped off into a residential area.  It's been there forever, I have an old map of my grandfather's that pre-dates I-295 when that freeway was just US 40 and simply an approach to the Delaware Memorial Bridge.  And, on that map, the Lander's Lane ramp is there!

I'm surprised myself that it is still open.

IIRC There are no advance signs only the exit sign near the ramp.
Title: Re: How many Interstate Exits are there?
Post by: Alex on July 09, 2009, 06:05:03 PM
My colleague found a web site that indicates that there are over 17,000 exits. Does that sound about right?
Title: Re: How many Interstate Exits are there?
Post by: Chris on July 09, 2009, 06:16:48 PM
I once collected all freeway exits in greater Los Angeles, and there were over a thousand of them in that area alone...
Title: Re: How many Interstate Exits are there?
Post by: City on July 09, 2009, 10:17:49 PM
Quote from: ChrisI once collected all freeway exits in greater Los Angeles, and there were over a thousand of them in that area alone...

If that's true, imagine New York City! :-o
Title: Re: How many Interstate Exits are there?
Post by: Jim on July 09, 2009, 11:03:20 PM
It seems the highway browser might help get a pretty good estimate.  For those who don't know:

http://cmap.m-plex.com/hb/selecthwys.php (http://cmap.m-plex.com/hb/selecthwys.php)
Title: Re: How many Interstate Exits are there?
Post by: Chris on July 13, 2009, 12:40:33 PM
There are ofcourse, more exits than that, because the US road network also has many freeways that do not carry an Interstate designation. Some metropolitan areas have relatively few Interstate Highways, such as New York or Phoenix, with many US Highways, State Routes and Reference Routes build with freeway standards.
Title: Re: How many Interstate Exits are there?
Post by: florida on July 13, 2009, 01:30:52 PM
True, also there are major roads which have interchanges where they intersect, but aren't shown as having any on a map.