Originally Posted by
Dr. HFH
In the past, weren't there two or three cities globally where different airports were considered co-terminus, so arriving at one and departing from the other didn't burn a segment? Yes, I know, I'm showing my age here . . . .
I believe this was the case but went away with the introduction of mandatory e-ticketing.
I had a paper ticketed DONE where the routing was ORD-LON-DBV being two of the (then) twenty segments which was was actually ORD-LHR,LGW-DBV. These days it may be considered three segments.