Piperboy, the French require that you file a flight plan when crossing their border in any direction which must also contain your FIR crossing point and estimate. In my case going from and to the UK my FIR crossing point was DEVAL.
Once in Spain it gets worse as every flight, even VFR, requires a flight plan to be filed! Dead easy though and once at San Sebastián I just wrote 'DCT LEDA' as my route!
Regards
UA