Longest stretches of X-lane freeway?

[Ellie]

Was wondering the other day about the longest stretches of freeway that is at least a certain number of lanes, especially since many freeways between large cities do go down to two-lanes in rural areas (such as I-5 in the Central Valley or I-45 between Dallas and Houston).

A few three-lane contenders:
* I-35 between San Antonio and the split of I-35E and I-35W (perhaps all of I-35E is three lanes now? last time I drove it was being widened, and Google Maps doesn't have anything more up-to-date)
* I-80 between Toledo and Youngstown
* I-75 between Troy OH and... some point in Kentucky? Don't remember if there are any gaps on the way to Lexington.
* Ontario 401 between London and Cobourg

Totally sure I'm missing some though, only listed routes I've driven myself.

Being relatively lenient with the rules here; going down to one lane is fine as long as it's only for a ramp when a route enters/exits another one (though not sure if any freeways that would make this list otherwise would run into that as an issue).

[CtrlAltDel]

* I-75 between Troy OH and... some point in Kentucky? Don't remember if there are any gaps on the way to Lexington.

I-75 is six-laned all the way to about mile 40 or thereabouts in Kentucky.

[wriddle082]

* I-75 between Troy OH and... some point in Kentucky? Don't remember if there are any gaps on the way to Lexington.

I-75 is six-laned all the way to about mile 40 or thereabouts in Kentucky.

The only exception is the northern 64/75 split, where both I-75 ramps are two lanes.  Also the 71/75 interchange in Downtown Cincinnati just north of the Brent Spence Bridge may also carry I-75 traffic on two lane ramps.  But not counting those, yes six lanes to just north of Corbin, KY.

But the granddaddy of them all may be I-75 from Naples, FL to at least Macon, GA.  If they have filled in the gaps just north of Downtown Macon, then that extends all the way to Ooltewah, TN.  Nearly 730 miles.

[pderocco]

I-15 is 14 lanes for 14.6 miles in San Diego County. That includes four segregated express/toll lanes.

[CtrlAltDel]

* I-75 between Troy OH and... some point in Kentucky? Don't remember if there are any gaps on the way to Lexington.

I-75 is six-laned all the way to about mile 40 or thereabouts in Kentucky.

The only exception is the northern 64/75 split, where both I-75 ramps are two lanes.  Also the 71/75 interchange in Downtown Cincinnati just north of the Brent Spence Bridge may also carry I-75 traffic on two lane ramps.  But not counting those, yes six lanes to just north of Corbin, KY.

Oh, yes.

But the granddaddy of them all may be I-75 from Naples, FL to at least Macon, GA.  If they have filled in the gaps just north of Downtown Macon, then that extends all the way to Ooltewah, TN.  Nearly 730 miles.

The part just south of the northern junction with I-475 is four lanes. I don't there are plans for that to change anytime soon.

[hotdogPi]

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