Main Page

The Algorithm

Coordinates for Portland on January 1, 2008 (taken from this tool)

NoTerminal and Drache at the February 17th coordinates

What is this?

XKCD comic #426 contains an algorithm that generates random coordinates across the country¹ every day.

These coordinates can be used as destinations for adventures, a-la Geocaching. They can also be used for local meetups.

For a little more interactive discussion consider joining the #geohashing IRC channel on Foonetic.

^1. Europe/Asia date handling still under discussion, see Talk:Main Page.

How it works

Play with the coordinate calculator here: http://xkcd.com/geohashing

Every day, the algorithm generates a new set of coordinates for every region. They are randomly placed -- they could be in the forest, in a city, or on a mountain. You can use this wiki to document the coordinates (geohashes) you've been to.

Unless you can predict the stock market, you can't figure out what the coordinates will be ahead of time. You can first calculate a weekday's coordinates at about 9:30 AM, and on Friday morning you can calculate the coordinates for each day that weekend.

If you go on Saturday afternoons, you might encounter other xkcd readers. Bring games!

When the coordinate falls somewhere dangerous or illegal to reach, use your judgment. If the coordinates are in an obviously unreachable place, the meetup is postponed until a better day.

Official Meetup

The official xkcd meetups happen every Saturday afternoon at 4:00 PM (local destination time). If the coordinates for your area are in the ocean, a military base, or somewhere otherwise unreachable, that meetup is of course postponed. Unless, of course, you own a boat, are a soldier at said military base, or are James Bond. If you can, record who's there, take pictures, and post them here.

Implementation

A sample interactive coordinate calculator can be found here: [1] A reference implementation is available here: view download

Active Graticules

- Region/Graticule pages named "City Name, Country (or state)" where "City Name" is the most major (by population) urban center contained within it.

Australasia

-32, 115 (Perth, Australia)

-13, 130 (Darwin, Australia)

-35, 138 (Adelaide, Australia)

-38, 145 (Melbourne, Australia)

-43, 147 (Hobart, Australia)

-35, 149 (Canberra, Australia)

-34, 151 (Sydney, Australia)

-28, 153 (Brisbane, Australia)

Europe

West to East (and North to South):

64, -21 (Reykjavik, Iceland)

55, -3 (Edinburgh, United Kingdom)

51, -1 (Swindon / Oxford, United Kingdom)

51, -0 (London West, United Kingdom)

51, 0 (London East, United Kingdom)

48, 2 (Paris, France)

51, 4 (Rotterdam / Antwerpen, Nederland / Belgium)

52, 5 (Midden Nederland)

51, 5 (Eindhoven, Nederland - plus wat België)

57, 9 (Aalborg, Denmark)

63, 10 (Trondheim, Norway)

55, 12 (Copenhagen, Denmark)

52, 13 (Berlin, Germany)

55, 37 (Moscow, Russia)

North America

West to East (and North to South):

61, -149(or -150) (Anchorage, Alaska)

47, -122 (Seattle, WA)

45, -122 (Portland)

37, -122 (San Francisco)

34, -118 (Los Angeles)

43, -117 (Boise, ID)

33, -117 (Santa Ana, CA)

33, -112 (Phoenix, AZ)

33, -111 (Mesa-Scottsdale-Chandler)

32, -110 (Tucson, AZ)

40, -111 (Salt Lake City, Utah)

50, -105 (Regina, Saskatchewan, Canada)

40, -105 (Denver, Colorado)

32, -97 (Ft. Worth, Texas)

30, -97 (Austin, Texas)

32, -96 (Dallas, Texas)

30, -96 (College Station, Texas)

41, -96 West of 56th St; 41, -95 East of 56th St. (Omaha, NE)

29, -95 (Houston, Texas)

45, -93 (Minneapolis NW, Minnesota)

44, -93 (Minneapolis SW, Minnesota)

38, -91 (St. Louis, Missouri)

41, -87 (Chicago)

39, -86 (Bloomington, Indiana)

36, -86 (Nashville, Tennessee)

34, -86 (Huntsville, Alabama)

42, -85 (Grand Rapids, Michigan)

33, -84 (Atlanta, GA)

36, -86 (Nashville, TN)

39, -84 (Cincinnati, Ohio)

42, -83 (Detroit, MI)

41, -83 (Toledo, OH)

41, -82 (Cleveland, Ohio)

41, -81 (Mentor, Ohio)

28, -81 (Orlando, Florida)

35, -80 (Charlotte, North Carolina)

25, -80 (Miami, Florida)

43, -79 (Toronto, Ontario, Canada)

38, -76 (DC east of 4th St {N/S}E, Bowie MD)

38, -78 (Shenandoah Valley, Virginia)

38, -77 (NW and SW DC, Northern Virginia, Bethesda MD)

35, -78 (Raleigh, North Carolina)

43, -77 (Rochester)

37, -77 (Richmond, Virginia)

39, -76 (Baltimore, Maryland)

45, -75 (Ottawa, Ontario, Canada)

40, -75 (Allentown, PA)

39, -75 (Philadelphia, PA)

40, -74 (Newark, NJ)

39, -74 (Atlantic City, NJ)

42, -73 (Albany, New York)

40, -73 (New York City)

42, -72 (Springfield, Massachusetts)

41, -72 (Hartford, Connecticut)

42, -71 (Boston)

41, -71 (Providence, Rhode Island)

44, -63 (Halifax, Nova Scotia, Canada)

39, -94 (Kansas City, Missouri)

21, -103 (Aguascalientes, México)

36, -115 (Las Vegas, Nevada)

Recent Events

2008-05-17 37 -122 -- Dan, Emad, and Randall reached the San Francisco coordinates in a successful test.

2008-02-24 45 -122 -- NoTerminal and Drache reached this point as part of an early test while coming up with the algorithm.

Next Upcoming Day

2008-05-21 -- The coordinates for Wednesday, May 21st are available.

Next Saturday

2008-05-24 -- The coordinates for Saturday, May 24th will become available on Friday about 9:30 AM EDT, when the Friday Dow Jones opening price is published.

see TimeandDate.com for dow opening time in local timezones

Related Projects

Geocaching: Global GPS cache hunt

Geodashing: Monthly points, randomly created

The Degree Confluence Project: visiting every integer latitude/longitude crossing point in the world