* Rumsey Historical Maps: 16 maps that show different regions of the world between 1680 and 1892. If you want to see more maps from David Rumsey Historical Map Collection, you can visit this site.
* Tracks 4 Africa: roads, points of interests and beautiful pictures from Africa. You can use it to learn more about this continent.
* Spotlight on Africa: flags and information from CIA World Factbook for each African country.
* National Geographic Quiz on Africa: test your Africa IQ, by answering 10 multiple-choice questions. If you can't find this layer in Google Earth, you can add it from here.
* European Space Agency: interesting images of the Earth seen from space.
All these layers and many others can be found in the Layers sidebar, Featured Content section.