We left Bangor in the afternoon when the wind had moderated and the sun had appeared, and went south through the Donaghadee Sound. Soon a light mist obscured the sun and we were gradually enveloped in a thickening fog. Given confidence from picking up an offshore fairway buoy in the fog after three miles on a compass course, we continued for another four miles. On checking our GPS position, we knew we were very close to Portavogie Harbour but could not make out any shoreline. Then breaking water and surface rocks were sighted close to in shallowing water, and we were not happy. Having only a passage (not detailed) chart we decided there was no case for casting about in such conditions, and got on the VHF to contact a fishing boat which was harbour bound under radar. She directed us out into safe water, steamed up astern, and led us into harbour – the pierhead looming up out of the fog at 100m distance. When the fog thinned, we found this fine fellow standing at the harbour head.