? So there is a point of no return?
No. A GA can be flown from any point, even over the runway. The flight profile would be as for a takeoff, assuming similar aircraft weight, which would be most likely as any heavier wt takeoff has to account for engine failure.
There is a ‘point of no return’ when approaching from the south, approx 11 miles (
PR 12-10), or GA
PR 8O8-810 if you choose, descend into, the wrong valley; cannot out-climb the terrain, nor turnaround; hence a guide pilot for first time visitors.