  We explore the atmospheric and surface history of a hypothetical paleo-Venus
climate using a 3-D General Circulation Model. We constrain our model with the
in-situ and remote sensing Venus data available today. Given that Venus and
Earth are believed to be similar geochemically some aspects of Earth's history
are also utilized. We demonstrate that it is possible for ancient Venus and
Venus-like exoplanetary worlds to exist within the liquid water habitable zone
with insolations up to nearly 2 times that of modern Earth.
