yea, but some of that land is near railroad tracks! better drop your estimate to about 5 billion. -----Original Message----- From: geocaching-bounce@xxxxxxxxxxxxx [mailto:geocaching-bounce@xxxxxxxxxxxxx] On Behalf Of GC-RGS Sent: Wednesday, May 19, 2004 9:24 PM To: GC-maillist Subject: [GeoStL] Here's some usefull information.... Earth has a surface area of 0.510 x 10^15 m^2 Assuming that 75% of the earth's surface is water, that's .128 x 10^15 m^2 of hidable space (not counting five star scuba or buoy caches). This converts to 49,400,000 square miles. Due to the 0.1 mile rule, you can only hide (roughly) 130 caches in a 1.06 mile by 1.05 mile area (1.113 square miles). That means we only have enough land area to hide about 5.77 billion caches. So, start hidin' them caches before it's too late! Rich