Adoption of wide (rectangular) vs. square route markers?

[hbelkins]

After seeing more and more photos of three-digit state and US routes in Iowa being signed with ovals/ellipses (state) or wide shields (US), I'm curious as to when and why states moved away from the square markers.

In Kentucky, the changeover came in the 1970s in concurrence with the adoption of the "honeycomb" reflective sheeting. Prior to that, Kentucky used square blanks (typically 24" x 24") for it's three- and four-digit state routes and three-digit US routes.

Until recently, District 12 continued to use circles-in-squares for four-digit state routes, but they've been moving toward the ellipsis/oval shape. I've also seen some wide US route markers for US 119 and US 460. Districts 4 and 8 continue to use circles for three-digit routes but the ovals/ellipses for four-digit routes.

I've seen a few older Ohio route markers that used a square for three-digit state routes, but those all seem to be going by the wayside.

Again, when did most states switch over, and why? Was there an MUTCD mandate?

My preference is for square blanks. Makes for a cleaner, more symmetrical marker assembly. Seeing all those wide US 151 and US 218 signs that had been installed in Iowa on my last trip there was a real downer.

[Scott5114]

If I remember correctly, the MUTCD first introduced the wide markers in the 1971 edition. I don't know that there was ever anything saying you had to use them, but the existence of the wide blank as an option pretty much implied that was the preferred method of signing 3-digit routes, and the states started using them of their own volition.

As for the why, using wide shields allows you to use wider series of digits, like Series D, for more routes. That's important because wider series digits are more legible as narrower ones at the same character height. (This is not my personal preference speaking–there is engineering data on this.) This is likely also why the MUTCD revised the US route shield shape in 1971 to not curve in so much at the top. So while the pre-1971 shields look nicer aesthetically, the 1971-spec shields perform better, and that's all that ever matters to FHWA.

Confusingly, up to the Clearview era TxDOT would frequently swap the Interstate shields around, using the wide Interstate shield for two-digit routes and the narrow one for three-digit routes. I have never read an explanation for what that was trying to accomplish.

[Revive 755]

The use of the wider markers for three digit routes is close to a mandate for US routes in the 2009 MUTCD:

A 24 x 24-inch minimum sign size shall be used for U.S. route numbers with one or two digits, and a 30 x 24-inch minimum sign size shall be used for U.S. route numbers having three digits.

State Route signs shall be designed by the individual State highway agencies.

Guidance:
State Route signs (see Figure 2D-3) should be rectangular and should be approximately the same size as the U.S. Route sign. State Route signs should also be similar to the U.S. Route sign by containing approximately the same size black numerals on a white area surrounded by a rectangular black background without a border. The shape of the white area should be circular in the absence of any determination to the contrary by the individual State concerned.

I suppose if a state really wanted to, they could use a 30x30 or larger shield for the three digit marker to keep the square shape.

[J N Winkler]

If I remember correctly, the MUTCD first introduced the wide markers in the 1971 edition. I don't know that there was ever anything saying you had to use them, but the existence of the wide blank as an option pretty much implied that was the preferred method of signing 3-digit routes, and the states started using them of their own volition.

Yes, the wide three-digit format was added to the MUTCD in 1971 along with a bunch of symbol signs.  I haven't been able to establish how widely various states experimented with wider-than-square formats for route numbers with more than two digits before that year.  California did have wider formats not just for Interstates but also for US and state routes as far back as the late 1950's.

Confusingly, up to the Clearview era TxDOT would frequently swap the Interstate shields around, using the wide Interstate shield for two-digit routes and the narrow one for three-digit routes. I have never read an explanation for what that was trying to accomplish.

That switch applied only to guide-sign shields and the three-digit shields were also taller (36" for two-digit routes, 48" for three-digit).  The real puzzle is why three-digit routes were deemed to require greater conspicuity.

[US71]

Iowa still mostly uses circles for 3d State Routes, though I've see an few ovals as of late.

[wanderer2575]

For some time, the original signing of M-553 in the Upper Peninsula was Michigan's only use of rectangular blanks for a 3-digit state trunkline.  When the route was extended to US-41, square blanks were used.  But a couple recent sign replacement projects have used rectangular blanks, so it appears that may be a new state standard.

(ETA:  The use of wide shields for 3-digit routes on BGSs has been a standard for quite some time.)

[MNHighwayMan]

Iowa still mostly uses circles for 3d State Routes, though I've see an few ovals as of late.

I'm pretty sure they're getting phased out for ovals. All new signs I've seen for three-digit state routes in the last few years (sign in linked pic is from last year) are rectangular.

[wriddle082]

When SC changed their state route marker nearly a dozen years ago, they use nothing but wide rectangular blanks, even for 2- and 1-digit routes.  Though I have seen a few square SC 9 shields in Chester and Union Counties, and I think square SC 5 shields in York County, those are definitely the exceptions.

[PHLBOS]

During and/or up through the early 70s, MA used square signs for its trailblazer/reassurance route markers; but all BGS-mounted state route shields were rectangular... even for one & two-digit routes.

Circa 1973(?), BGS-mounted square shields for one & two-digit routes as well as three-digit routes containing two 1s in them (i.e. 11X, 1X1) started being used.

For trailblazer/reassurance markers, rectangular shields for 3-digit routes started appearing around the mid-70s; although square shields for 3-digit routes containing at least a 1 in the route number (most 3-digit MA routes are 1XX) were still periodically used.  Note: these square & rectangular shields were all larger than the earlier-used square shields.

Rectangular route shields for all 3-digit routes in MA for trailblazer & reassurance markers became the established norm by the early 1980s.

[hbelkins]

When SC changed their state route marker nearly a dozen years ago, they use nothing but wide rectangular blanks, even for 2- and 1-digit routes.  Though I have seen a few square SC 9 shields in Chester and Union Counties, and I think square SC 5 shields in York County, those are definitely the exceptions.

Tennessee does the same, as you know, for its primary route markers, but that's probably due more to the width of the state so the outline can more easily fit into the blank. Compress it to fit a square blank, and the state outline probably wouldn't be tall enough to put the lettering of the state name inside.

The use of the wider markers for three digit routes is close to a mandate for US routes in the 2009 MUTCD:

A 24 x 24-inch minimum sign size shall be used for U.S. route numbers with one or two digits, and a 30 x 24-inch minimum sign size shall be used for U.S. route numbers having three digits.

State Route signs shall be designed by the individual State highway agencies.

Guidance:
State Route signs (see Figure 2D-3) should be rectangular and should be approximately the same size as the U.S. Route sign. State Route signs should also be similar to the U.S. Route sign by containing approximately the same size black numerals on a white area surrounded by a rectangular black background without a border. The shape of the white area should be circular in the absence of any determination to the contrary by the individual State concerned.

I suppose if a state really wanted to, they could use a 30x30 or larger shield for the three digit marker to keep the square shape.

Can't tell you how interesting I found this, given that US routes have no official federal government sanction, since they're under the auspices of AASHTO. ("It's not a federal route, Calrog!!!!") Yet the federal government issues specs for a route system it doesn't govern.

[J N Winkler]

I'm pretty sure they're getting phased out for ovals. All new signs I've seen for three-digit state routes in the last few years (sign in linked pic is from last year) are rectangular.

Iowa DOT has had standard plan sheets for three-digit route markers in its signing plans sets for several years now (there is typically one or two pure signing contracts in each month's letting).  I also think they are phasing out Interstate shields to the 1958 design in favor of the current one.

I do find it a little odd that IDOT is still clinging to Series B digits even in wide guide-sign shields, though to be fair, this is what the plan sheets show and may not necessarily be making it out into the field.

[MNHighwayMan]

I do find it a little odd that IDOT is still clinging to Series B digits even in wide guide-sign shields, though to be fair, this is what the plan sheets show and may not necessarily be making it out into the field.

Curiously, it is definitely making it out to the field. In fact, I see more of them with those Series B digits than without. It's almost like it's their standard, which... why bother with wide shields, then?

Example 1
Example 2
Example 3

I have more examples yet, too.

[jbnv]

Wide shields are an utter bane in Louisiana. There are enough problems with consistency with square shields alone. There's almost no need for wide shields here--four digits in Series B fit quite nicely in the "foot" of the outline--yet we have wide shields with plenty of whitespace to spare.

[Finrod]

The wide shields look silly for Georgia state routes, because they use an outline of the state for the state shields, so you end up with a fat Georgia outline.

[cjk374]

Wide shields are an utter bane in Louisiana. There are enough problems with consistency with square shields alone. There's almost no need for wide shields here--four digits in Series B fit quite nicely in the "foot" of the outline--yet we have wide shields with plenty of whitespace to spare.

LA can't even get the wide US signs to look worth a damn either.

[wriddle082]

The wide shields look silly for Georgia state routes, because they use an outline of the state for the state shields, so you end up with a fat Georgia outline.

On state outline shields, if said state has straight lines along most of its northern and southern borders, then they should simply lengthen those borders enough to fit the extra digits in.  AL, AZ, and MO don't seem to have a problem with this.  GA, however...

[bandit957]

My guess for Kentucky would be 1977. I do remember seeing a lot more square-sized markers when I was very young. But they were common in some parts of the state much later.

[bandit957]

Also, there was a time maybe 15 or 20 years ago when Kentucky's wide state route shields were starting to become very flat, almost rectangular. They looked absolutely ridiculous. There were some of these on the AA Highway.

But now, the trend is towards true ovals that are not flattened at all.

[US71]

Wide shields are an utter bane in Louisiana. There are enough problems with consistency with square shields alone. There's almost no need for wide shields here--four digits in Series B fit quite nicely in the "foot" of the outline--yet we have wide shields with plenty of whitespace to spare.

LA can't even get the wide US signs to look worth a damn either.

I've seen 3d US with smaller or skinnier numbers on a 2d shield, like 425

[wolfiefrick]

Up until the late 1990s, Missouri used squares for everything. Series B for 3-digit routes, and Series C for 2-letter supplemental routes.


Photo by Gerald Brown on Flickr

They have since shifted to using wide shields for long route numbers, but without compromising Missouri's distinctive outline. Since the northern and southern borders are essentially straight lines with the exception of the boot heel, they can just extend Missouri horizontally as opposed to stretching it.


Photo by me

[rarnold]

I do find it a little odd that IDOT is still clinging to Series B digits even in wide guide-sign shields, though to be fair, this is what the plan sheets show and may not necessarily be making it out into the field.

Curiously, it is definitely making it out to the field. In fact, I see more of them with those Series B digits than without. It's almost like it's their standard, which... why bother with wide shields, then?

Example 1
Example 2
Example 3

I have more examples yet, too.

Please, for the love of God, don't. I in no way condone shooting holes in road signs but I am willing to make an exception in this case. Those things are hideous, as are their US Route relatives.

[US71]

Former section of US 71 near Early, IA