I milled out the mountain “Matterhorn” from Switzerland. It turned out very well!
I downloaded the 3D data from this site: http://gdem.ersdac.jspacesystems.or.jp/
You could mill the whole World if you would want to.
I did it with these instructions: https://3drucken.ch/2012/07/relief-des-mont-blanc.html
but it is a German instruction. If anyone want to do a thing like that just say it and I will translate it into English.