A humanitarian air service is revising its surge-deployment plan: when a crisis hits a capital, the first flight goes to the nearest airport that already takes scheduled traffic, and the last leg is by road. The planners want the list of capitals where that road leg is long — more than 75 km, roughly an hour — because those are the ones that need a pre-positioned vehicle. You have the Natural Earth places and airports; both are global and neither is perfect.
Return the national capitals (capital = true) whose nearest civil mid-size or major airport is more than 75 km away, as points, carrying:
name, country — the capitalnearest_airport — the name of the closest qualifying airportdistance_km — great-circle distance to it, km, one decimalA qualifying airport is one whose type is major, mid, major and military or mid and military — a civil field with scheduled traffic. Military fields, small strips and spaceports are not on the list.
Distances are global, so they are geodesic: no single projected CRS works from Reykjavík to Funafuti. Measure on the sphere or the ellipsoid.
These are where the teaching is. Read them twice.
Nearest-airfield and last-mile-distance tables are the first product of humanitarian logistics planning, and the same method sizes rural ambulance and freight networks.
5 scored, 0 informational
How many capitals are beyond the threshold
40%Capitals returned as points
10%Carries name, country, nearest_airport and distance_km
20%The longest road leg in the set
20%Submitted in EPSG:4326
10%