Not just by sea. I know of a chap that spent 18 months walking to the south of France and then across the Pyrenees to be captured by the Spanish, escaped and smuggled by the British consulate to Gibraltar and then a RN ship to England. He was debriefed by MI9 to reveal a war crime and was awarded a Military Medal. His medals recently came up for sale and I'll spend the rest of my life regretting not buying them.
Another Example: In my father in law's unit 6th MAC RASC one of his fellow officers Lieutenant Chandos Sydney Cedric Brudenell Bruce The Earl Of Cardigan RASC was captured at 10 CCS Crombeke on 29 May 1940 and became a prisoner of war along with other officers of the unit Major H R Fosbery RAMC, 2nd Lt D J Hale RASC and 15 other ranks. However he managed to escape (not by sea) and made his way through Europe on foot down through France to Spain, all the while taking notes of his exploits which he published as a book in 1950 titled "I Walked Alone". When he returned to England he had a less active Army role and became an aeroplane instructor as he had been an amateur pilot before the war. Which also influenced my Father in Law who was the same age as Cedric, as when he was invalided out of the Army in March 1941 he joined the Air Transport Auxillary.
