Kenwood House

The cream-coloured mansion sits on Hampstead Heath looking like someone's just invited you round for afternoon tea. Kenwood House is an 18th-century country estate that feels properly removed from London despite being slap in the middle of it, and the gardens are genuinely worth the walk up from the Heath's lower slopes.

Inside, you'll find Robert Adam's plasterwork - all sweeping ceilings and elegant proportions - plus a decent art collection that won't exhaust you in an afternoon. The library is the real draw. It's the kind of room that makes you understand why people used to spend entire afternoons reading in their homes.

Historically-minded visitors will get the most from a guided visit, though the house itself doesn't require hours of your time. Families with older kids find it less exhausting than central London museums, especially if they combine it with a proper walk across the Heath. Younger children might find the interiors a touch dull after twenty minutes.

Admission's free, which is fair play given you're basically getting a stately home tour without the stately home prices. Allow an hour inside, maybe two if the weather's decent and you want to linger in the gardens. The real magic happens in summer when they host open-air classical concerts on the grounds - those are worth booking ahead for.

Lovat Parks, just five miles away, makes a solid base if you're staying nearby. The Heath itself is the main event; Kenwood's the bonus rather than the reason to visit.