Braintree Swimming Centre

The indoor pool here is a proper working facility - the sort of place where you'll see school groups and serious swimmers rather than tourists. It's in Braintree itself, bang in the town centre, and it's the kind of venue that serves the local community well without pretending to be anything fancy.

You get a 25-metre pool, which is decent enough for lengths or lessons, plus a smaller shallow pool that works well for younger kids or those less confident in water. Opening times vary by season, so you'll need to check ahead before you visit - it's not the sort of place that operates on a whim. Entry costs a few quid per person, and it's genuinely good value.

This works best if you've got children who need to burn off energy on a rainy day, or if you're based at one of the nearby caravan parks - Stocks Farm Camping and Golden Grove are both within easy reach - and want a half-day activity without travelling far. Gosfield Lake Resort is also close by, if you're considering that as your base instead.

Realistic timeframe? An hour, maybe ninety minutes if your kids are water babies. Don't expect slides or a splash pad - it's functional, not fun-fair territory. But on a grey Essex afternoon when the kids are climbing the walls of your caravan, it does the job properly.