View from the Window at Le Gras by Joseph Nicéphore Niépce (1765 – 1833) is the oldest surviving photograph (circa 1826).
The “window view is considered the oldest photograph that is known to have been formed in the camera in the world.” (widewalls.ch)
The exposure time was supposedly 8 hours long but studies found that, with Niépce’s technique at that time, the exposure time must have taken at least 8 hours, but rather several days.