Six Data Errors Later, a Digital Twin Yields Fiskardo's Real Evacuation Time

A geospatial analysis using pgRouting's Dijkstra algorithm was conducted to estimate road evacuation time from Fiskardo, a village on the Greek island of Kefalonia, in a wildfire scenario. The process uncovered six successive errors, including a stale road network table, a mislabeled cost column conflating meters with minutes, mismatched coordinate reference systems, and unsorted query results. A suspected connectivity gap in the coastal road data caused the router to favour a 29 km inland mountain route over a 15 km coastal alternative. After correcting all identifiable errors, the analysis concluded that evacuation to Agia Effimia Marina would take approximately 44 minutes across 116 road segments. The exercise highlights that in safety-critical geospatial work, a result's value lies in how rigorously it has been stress-tested, not merely in whether the query executes successfully.