The big one
A small vertical change moves the water a very long way sideways
That is the whole mechanism, and it explains almost everything people find surprising about a Zanzibar beach.
Why it happens
Zanzibar sits on a broad, shallow continental shelf fringed by coral reef. Along much of the east coast the seabed between the shore and the reef crest is a reef flat — very shallow and very gently sloping, sometimes for several hundred metres.
Combine a gentle slope with a large tidal range and the waterline travels an enormous distance horizontally for a modest vertical change. At low water you can walk out towards the reef on ground that was under a metre of sea a few hours earlier.
Where the shelf is narrower and the water deeper close in — most obviously at the northern tip — the same vertical range moves the waterline barely at all.
Which coasts, and how much
| Coast | Effect at low water | What it means for a day |
|---|---|---|
| North (Nungwi, Kendwa) | Minimal | Swim whenever you like |
| North-east (Matemwe and around) | Moderate to large | Swim around the tide; the reef is the compensation |
| East and south-east (Paje, Jambiani) | Large | Hours of exposed flat; the pool carries the afternoon |
| West and south-west | Variable, often moderate | Depends heavily on the specific bay |
What to do at low water
Walk out on the flat, which a great many people end up enjoying more than the swimming.
There are starfish, urchins, small fish trapped in pools, seaweed frames in rows, and villagers working the shallows. It is the most interesting half hour of the day on that coast and it is available to anybody willing to put shoes on.
Reef shoes are worth packing — coral fragments and urchins are the two reasons — and the walk back is always longer than it looked on the way out.
How to plan around it
- Ask for the tide times on your dates before booking. Any hotel can produce them in one email.
- Swim at high water, which moves by roughly an hour each day, so the good swimming hour drifts through the week.
- Use the pool in the middle of the day, which on the east coast is what it is for.
- Book boat trips and diving for high water, since some departures are tide-dependent.
- Walk the flat at low water rather than treating it as dead time.
Why hotels do not mention it
Mostly because it is entirely normal to everybody who lives there, in the way that nobody in Cornwall thinks to mention the tide.
And partly because a photograph taken at high water is the more flattering photograph, and nobody in the business of selling beach holidays has a strong incentive to publish the other one.
The result is a preventable disappointment, which is why this page exists.
The honest summary
The tide is not a problem with Zanzibar. It is a property of a reef coastline, and on the east coast it produces something a Caribbean beach cannot — a walkable reef flat teeming with things.
What it is not is a beach where you swim on demand. If that is what somebody in your party wants, go north, and do not let a photograph talk you out of it.
Ask what the tide will do on your dates
Our Zanzibar specialist replies within 24 hours with the coast that suits you and the tide times for your week.