Cueva Ventana

What the code says

The Grid Point Code for Cueva Ventana is #GHTM4-12R57. It names a cell 2.56 m north to south and 3.25 m east to west, centred on 18°22'18.01"N, 66°41'29.98"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

Cave in Arecibo, Puerto Rico

Code

#GHTM4-12R57

With a check character

#GHTM4-12R57*1

Short form

12R57

Cell centre

18.371670, -66.691661

Cell size

2.56 m by 3.25 m

Region

Arecibo

Country

Puerto Rico

How to give this address

On a sign, a form or a delivery note

The whole code, #GHTM4-12R57. It needs nothing else: no city, no street, no network to read it back.

Said aloud, in Arecibo

Cueva Ventana 12R57: 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 5.1 km east or west of Cueva Ventana. 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

#GHTM4-12R57*1. 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 50.7 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. MGHTMMetropolitan area40 km by 50.7 km
2. 4GHTM4District8 km by 10.1 km
3. 1GHTM41Suburb1.6 km by 2.03 km
4. 2GHTM412A few streets320 m by 406 m
5. RGHTM412RBuilding64 m by 81.1 m
6. 5GHTM412R5Entrance12.8 m by 16.2 m
7. 7GHTM412R57Doorway2.56 m by 3.25 m

More in Puerto Rico

• Plaza del Mercado de Ponce
• San Juan
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