This year will see many anniversaries in tidal science including the 100th anniversary of the Liverpool Tidal Institute, which could be said to be the predecessor of the National Oceanography Centre. The history of this subject is too large to cover in one talk (for an excellent book on the history of tides, see that by David Cartwright, CUP, 1999), so I will just pick out a few aspects that have interested me in recent years. These include how much the ancient Greeks knew about the tides, which is especially surprising given that tides are not very large around Greece; how tides were sometimes misunderstood by mariners on voyages of discovery, such as James Cook in the 18th century, even though they should have known better as it had been many years since Newton; and how the humble Liverpool tide table makers of the 18th century knew more about tides than most people. One recurring theme will be how certain aspects of the tides, especially diurnal inequality, had to be re-discovered through the years. The talk will conclude with an overview of tidal science in Britain in the 19th-20th centuries, eventually leading up to the founding of the Liverpool Tidal Institute by Joseph Proudman almost exactly 100 years ago today.