John lectures regularly on ships for Viking, Saga, Cunard and P&O. He also lectured on Voyages of Discovery, Voyages to Antiquity and Swan Hellenic.
Here is a list of ships that have engaged John:
- Adonia, Arcadia, Aurora, Azura & Oriana (P&O)
- Aegean Odyssey (Voyages to Antiquity)
- Minerva (Swan Hellenic)
- Queen Elizabeth, Queen Mary 2 & Queen Victoria (Cunard)
- Spirit of Adventure & Spirit of Discovery (Saga)
- Viking Jupiter, Viking Saturn, Viking Sea, Viking Sky, Viking Star & Viking Venus (Viking)
- Voyager (Voyages of Discovery)
John Sherlock 