I sailed from Norfolk, Virginia, to St. Thomas, Virgin Islands. When we were in the Bermuda triangle, our ship's compass starting veering to one side, then made complete 360 degree turns, then started spinning. We were passing a magnetic anomaly marked on the chart. Fortunately, over time, the compass corrected itself. If we had been in an aircraft with limited time and fuel, I don't know if the compass correction would have occurred in time for the aircraft to resume course and land.

Compass anomalies around there do seem well attested. Pretty plausible explanation for why things have gone haywire there. Not the only place.

I believe it is very hard to orientate yourself by landmarks around there too.