Utah/Naming Conventions/Activity

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Welcome to tonight's social gathering sub-activity!
Sub-activity name: 370 S. 300 E.: Utah's Unique Addresses
Sub-activity duration: One minute.
Sub-activity time: Each guest just notices the Salt Lake City street name signs sometime during the conference. Best tonight when downtown. We will try to point them out to guests during the evening. Guests also red all about the addressing system via this page.
Activity QR-code
QR-code for online version
Street name signs at the intersection of 500 N and 500 W in Salt Lake City
Street name signs at the intersection of 500 N and 500 W in Salt Lake City
A typical street grid you may find in a Utah city
A typical street grid you may find in a Utah city

370 S. 300 E.?

Here we are at the State of the Map U.S. 2024 Thursday, June 6 evening social event and Martijn van Exel is pointing out the street name signs outside the venue, 370 S. 300 E. Salt Lake City, Utah.

But what does that address mean? Does it mean that some of we serious map people might, Lord forbid, get lost trying to find it on our own?

Grid values as street names

Well, it turns out, in Utah, very often, the address grid values are the street names!

Utah addresses are unique from other states because of a strong address grid system [which] enables us to make special assumptions and optimizations[1]

Whereas in other states [2] you might have "Nibblesworth Avenue (700 East)", or "7th Avenue (700 East)", in Utah they mostly just simply toss out the window dressings, and all you have left is "700 East". Yet life somehow still manages to go on.

Origin point: Salt Lake Meridian and base line

OK, it's not the end of the world. But OK, where does it begin? Where's the 0 N. 0 E. origin point? This is the place, perhaps?.

Close, but it actually starts at the much smaller monument Meridian marker. Alas, temporarily closed in 2024.

Salt Lake City Base and Meridian monument
Salt Lake City Base and Meridian monument

In OSM data we actually find a second "correct position" node too, 2.3 meters to the southeast. (echo 40.7695353 -111.8913520 40.7695181 -111.8913354 | geod -f %.1f +ellps=WGS84 -I gives: 143.7 -36.3 2.369.)

  • Q: Actually wouldn't the Public Land Survey System (PLSS) corner be a few feet away, in the middle of the intersection, of South Temple and Main St.?
    • A: No. Looking at USGS topographic maps, you will see the PLSS is rather disassociated from the street grid of Salt Lake City! No PLSS on this plat.




  1. Q: What is the correct way to mentally parse "370 S. 300 E."?
    • A: 370 ( S ( 300 E ) ).
  2. Q: What would 370 S. 300 E. be in your home town?
    • A: 370 S. 3rd St. E. in mine. How about yours?
  3. Q: If you were to start over, how would you make Salt Lake City's street name / address system even more "powerful"? What would "370 S. 300 E." become?
    • A: 75000 + -370, 25000 + 300 => 74630 N. 25300 E.! Sort of like Edmonton, Alberta, but getting the most out of those five digits... But that's just one "solution"...
  4. Q: Locate 370 S. 300 E., given the locations of some nearby street corners.


Yes, in many parts of the world places unfortunately don't have address grids, or even addresses.



All that needs to be done:

  1. Staff includes the first page of this Utah/Naming_Conventions/Activity page in the printed conference materials, if any.
  2. Martijn et al. points out the 300 East street name sign outside the Thursday evening venue. Or if everybody is already inside, simply reminds them to be sure to notice the street signs while in town this evening. (True, the 400 S. sign at that intersection does have a nickname on it, in smaller letters, "University Blvd.".)
  3. Conference participants scan the QR-code in their leisure to see this full Utah/Naming_Conventions/Activity page.

Welcome to reuse this page, editing it for future activities.