Grid Point Code

Play

Half Dome

near Mammoth LakesCaliforniaUnited States

With a code
#G0P04-56LNM
Said aloud
Half Dome 56LNM

Open in the playground

What the code says

The Grid Point Code for Half Dome is #G0P04-56LNM. It names a cell 2.56 m north to south and 2.70 m east to west, centred on 37°44'45.62"N, 119°31'59.39"W, and it turns back into that cell on any phone or computer by arithmetic alone: no network, no account, no lookup table.

What it is
Granite dome in Yosemite National Park, California
Code
#G0P04-56LNM
With a check character
#G0P04-56LNM*9
Short form
56LNM
Cell centre
37.746006, -119.533164
Cell size
2.56 m by 2.70 m
Region
California
Country
United States

How to give this address

On a sign, a form or a delivery note

The whole code, #G0P04-56LNM. It needs nothing else: no city, no street, no network to read it back.

Said aloud, in California

Half Dome 56LNM: a name both people know, then the last five characters. They give back the exact code for anywhere within 4.0 km north or south and 4.2 km east or west of Half Dome. Further away the same five name somewhere else, which is why the whole code is what goes on a sign.

Copied by hand, or read over a phone

#G0P04-56LNM*9. The character on the end catches any single mistyped symbol and any two neighbours swapped.

As a link or a square code

Open it on the map, move to the exact door, and add directions if the code needs help: "blue gate, second floor". The link and the square code carry them. Nothing is kept on this site.

From the city to the door

The first four characters name a cell about 40 km by 42.3 km here. Each one after that picks one of 25 inside the last, so the whole ten name a spot about the size of a doorway.

  1. G0P0Metropolitan area40 km by 42.3 km
  2. G0P04District8 km by 8.45 km
  3. G0P045Suburb1.6 km by 1.69 km
  4. G0P0456A few streets320 m by 338 m
  5. G0P0456LBuilding64 m by 67.6 m
  6. G0P0456LNEntrance12.8 m by 13.5 m
  7. G0P0456LNMDoorway2.56 m by 2.7 m

More in United States

Place and region from Wikidata, described on Wikipedia; nearby town from GeoNames, under CC BY 4.0.