Winston Churchill Avenue
provides access to the British Overseas Territory of Gibraltar. The road intersects with the main (and only) runway at Gibraltar International Airport. When commercial and military planes land, traffic is stopped and security barriers are put up to keep vehicles from crossing. Though plans for a tunnel under the runway are in the works, Churchill Avenue is currently the only way to get from Spain to Gibraltar, so there's no way to avoid the runway. Traffic stops for a few minutes at a time whenever a plane lands.
Despite repeated delays, a new under-airport tunnel is slated for completion in late 2018. Luckily, the airport is not overly busy, with several hundred "movements" (takeoffs and landings) each month, peaking during summer vacation season. There's really no way around this unusual intersection. The isthmus that connects the territory to Spain is the only space flat enough for a runway in Gibraltar, and the only place to realistically build a cross-border roadway.