I use geopo rather than geohash: http://geopo.at/intl/en/developer/ http://geopo.at/intl/en/developer/ Can't remember why (the database schema calls the column

I use geopo rather than geohash: http://geopo.at/intl/en/developer/ http://geopo.at/intl/en/developer/ Can't remember why (the database schema calls the column geohash) but it is great in either system to be able to do a really fast lookup based on a substring and then use proper distance algorithms to narrow down to what's actually close. You need to over shoot as mentioned in the Geohash article because boundaries could be very close to the position.