Also remember that a lot of the coastlines of yesteryears are now underwater, and coasts tend to be good for fishing and Homo habitation. So, there may be sites

Also remember that a lot of the coastlines of yesteryears are now underwater, and coasts tend to be good for fishing and Homo habitation. So, there may be sites, just 200m down and buried in sediments. Also, humans tend to scavenge older sites and many places still may be the sites of current metropolises. Just as they were good places to settle way back when, they are good to settle now. Essentially, many theories are valid as there is not enough evidence to really support one side or the other. New techniques like geo-spatial mapping satellites may help, as will others that are not yet invented. Google Earth has been a (possible) asset to this and people may have found some new Egyptian sites using it : http://news.sky.com/story/two-new-pyramids-found-on-google-earth-10473190 http://news.sky.com/story/two-new-pyramids-found-on-google-e...