History of UFOs, Sightings and Encounters

http://www.xfacts.com/old, http://www.ufoevidence.org/topics/general-ancientastronauts.htm
Ancient astronauts or space travellers since ancient times, the mystery continues.

http://www.history.com/topics/history-of-ufos, http://www.ufosnw.com/history.htm

http://www.bibleufo.com/ufos.htm
Its much easier for many people to believe that intelligent life only developed on just one planet.
http://www.crystalinks.com/ufohistory.html

http://www.ufoevidence.org/documents/doc154.htm

http://www.telegraph.co.uk/news/picturegalleries/howaboutthat/3447508/UFO-sightings-140-years-of-UFO-pictures.html

From the elusive past to more recent incidents there is http://inexplicata.blogspot.com
Inexplicata remains as one of the best places to explore this intriguing phenomenon.
https://www.facebook.com/InexplicataTheJournalOfHispanicUfology

http://desert-shapes.blogspot.ca/2014/05/is-there-deep-underwater-base-near.html