Chart correction 1799 — chart 1664
Chart 1664 (INT 1954) [ previous update 1719/25 ] UNDETERMINED DATUM Insert 55,Obstn 12° 14´·8N., 17° 30´·1W. 117-Obstn 12° 02´·3N., 17° 29´·2W.
Source: UKHO Admiralty Notices to Mariners
Reference information — always verify against official Notices to Mariners before navigation.