From Martin Gregorie
It is not only satellite navigation that blanks out the island of Foulness, off the UK’s Essex coast (Feedback, 27 May). Searching for it on www.multimap.co.uk points you to a stretch of the Market Weighton Canal in east Yorkshire, and also to an area of the foreshore off Cromer, which is in Norfolk and also miles from the muddy Essex coast. However, Foulness is on the map itself if you know where to look, and it is indexed properly on www.streetmap.co.uk and on the Ordnance Survey’s own site. So the sat-nav conspiracy may be more of a cock-up.
Harlow, Essex, UK
