Poole is often filed as “the one next to Bournemouth with the expensive houses”, which undersells it considerably.
A harbour that is genuinely remarkable
Roughly 36 square kilometres at high water, which puts Poole Harbour among the largest natural harbours in the world. It is also almost absurdly shallow, mostly under two metres, which is why it stays flat in a blow and why half the south coast learns to sail on it.
An island that changed the world, slightly
Brownsea Island sits in the middle of it. Baden-Powell camped there in 1907 with twenty boys, and that camp is generally treated as the start of Scouting. The island also kept its red squirrels when most of England lost theirs.
Habitats that barely exist elsewhere
The harbour is a RAMSAR wetland holding tens of thousands of birds through winter. The heath around it is rarer than tropical rainforest. See wildlife.
A town built on salt cod
The Georgian Old Town was paid for by the Newfoundland fisheries, and it is one of the better-preserved historic quarters on this coast. The Cockle Trail walks you through it for nothing.
And, yes, the beaches
Blue Flag sand at Sandbanks, with the Jurassic Coast beginning four minutes away across the harbour mouth.
Start here: things to do in Poole.