The sea makes up 70% of the earth! Also, there might be places we haven't discovered too small to see from space!
I think your answer would be Department of Housing and Urban Development.
President Abraham Lincoln
While there was slavery in the past in European nations as well, it wasn't as rampant as it was in the United States where there were a lot of plantation owners who also owned multiple slaves and whole families at times - before this was made illegal during the US civil war.
