back of beyond
Extremely remote. For example, John's about to move to some tiny island, truly back of beyond. This term, used as a humorous exaggeration, relies on the meaning of beyond (or the beyond) as "a distant place, beyond human experience." [Early 1800s]
| an extraordinary or unusual thing, person, or event; an exceptional example or instance. |
| a screen or mat covered with a dark material for shielding a camera lens from excess light or glare. |