Spend a weekend in Diane Keaton's idyllic cottage

Diane Keaton is so taken with this cottage and its enchanting location, she wishes she could buy it. Fortunately, she can't because Ferry Cottage belongs to the National Trust, which is why I'm spending the weekend here, sunning myself alongside the ducks in my pjs.

Keaton was here last summer to film Hampstead, which arrives in cinemas this weekend. As the title indicates, it's mostly set in North London, but at the end of the film Keaton's character moves to this cottage. I won't spoilt it further except to say it's a rom-com and the leading man is Brendon Gleeson who plays a tramp (read our review).

https://www.youtube.com/watch?v=FOeXWxl0axc

What you don't see in the film is that Ferry Cottage is tucked away in a secluded corner of a National Trust estate. It's one of two riverside cottages available to rent in the grounds of Cliveden House (pronounced "cliff-den"), an imposing stately home with impeccably manicured gardens and a colourful history in Buckinghamshire, near Maidenhead.

One of the joys of staying here is that you get the woodlands and gardens almost to yourself first thing in the morning and when the gates close at 5.30pm. So after I've finished my pot of earl grey, I decide to make the most of the privileged access with a morning run: up, up, up through the woods, past a grass amphitheatre (pause to catch my breath and admire a panoramic view of the river), past a grand stone pavilion, past giant topiary ducks and sculptures of baboons in the Long Garden, past the Fountain of Love with its frolicking naked ladies and cherubic angels.

By now the sun is high in the sky so I sidestep the grand driveway and keep to the shade of an orderly line of trees as I approach the house, which is a luxury hotel nowadays. Sweaty wave to a doorman in top hat and tails, then round the back to a 110 metre-long, 8 metre-high terrace where I stop to drink in the view.

The parterre at Cliveden

One of the early owners of Cliveden lopped the top off the hill to create a parterre: a four-acre grass platform with a central avenue bordered by intersecting triangular beds of colour-coordinated flowers. Beyond it sparkles a curl of the river and lush wooded countryside stretches out as far as the eye can see.

By now my face is an unflattering shade of crimson and I begin to worry I'll alarm the hotel guests, so I spoil the view by lumbering down the central avenue and descending a long staircase, which delivers me back to the river and my tranquil abode. It certainly beats running round South London.

Keaton enjoys her riverside cottage in Hampstead

By the time I've cooked brunch and meandered back up to the parterre, the day-trippers have arrived. Cliveden is the National Trust's second most popular attraction – only beaten by the Giant's Causeway in Northern Ireland. But even on a sunny afternoon in June, it's easy to escape the picnicking families flocking to the Water Garden and a huge yew maze, which is an exact replica of the one belonging to the American multimillionaire William Astor who bought the estate in 1893.

I make a beeline for one of the free talks about the history of the house (you can also do a tour on Sunday afternoons). Its most famous resident was William Astor's daughter-in-law Nancy Astor, who threw legendary parties and became Britain's first female MP. Her predecessor, the Duchess of Sutherland, was a great friend of Queen Victoria's. She had the cottages built so Her Majesty could arrive by boat from Windsor Castle and dine by the river – just like Diane Keaton and me.

I while away the rest of the afternoon listening to a jazz band in the Ibex Grove and exploring the woodland walks. You can hire little boats by the hour, but I'm content watching them. In fact, that's my favourite thing to do: basking in the sunshine on my patio as the speedboats, barges, rowing boats and kayaks glide past.

Brendan Gleeson and Keaton sail down the Thames

I spy a kingfisher and a heron. Red kites arc in the sky. Every now and then there's a splash as a dog on the path on the opposite bank wades happily into the river, and more than one owner ends up drenched too. As dusk falls, the ducks fly upstream and the birds trill their final choruses. The swan has found her mate and five fluffy cygnets.

In Jerome K Jerome's 1889 novel Three Men in a Boat, he described Cliveden Reach: "unbroken loveliness this is, perhaps, the sweetest stretch of all the river".

128 years on, it's as lovely as ever.

Essentials:

The gardens at Cliveden are open every day from 10 to 5.30pm and cost £13 for adults and £7 for children. Claire Webb stayed at Ferry Cottage, which sleeps four. At this time of year, prices start at £845 for three nights. To book, go to nationaltrustholidays.org.uk.

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