Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.
Q: The Geysers were first seen by Euro/Americans and named in 1847 during John Fremont's survey of the Sierra Mountains and the Great Basin by William Bell Elliot who called the area ''The Geysers,'' although the geothermal features he discovered were not technically geysers, but fumaroles.
A:
When was the The Geysers discovered?