Hands-on museums and science centres. Several of the best ones are free.
A big hall of British lorries, buses and fire engines in the town that built Leylands, with a lorry driving experience for kids and a cafe for the grown-ups. Gift Aid your ticket and it becomes a 12-month pass for nothing extra.
Free, indoors and better than it sounds: interactive science aimed at younger children, glassblowing demos, a picnic area and a small playground outside.
Five floors, free, and it covers three things small children reliably love: giant dinosaurs, an aquarium and a space gallery. The best wet-weather day within half an hour.
Hands-on science galleries and a glass rooftop observatory over the Mersey. Small, cheap, indoors and close.
Working steam engines, the story of Cottonopolis, and hands-on galleries in the world's oldest surviving passenger railway station. Free, and the live demonstrations are the bit kids actually remember.
A T. rex skeleton cast, live frogs in the vivarium, Egyptian mummies and a genuinely good natural history floor. Free, university-run, and less overwhelming than the big London equivalents.
Shirts, trophies and match footage across six floors, with penalty shootout and skills games that football-mad kids refuse to leave. If yours do not care about football, skip it - it is exactly what it says.