Where should I take 9 year old DD on holiday?

[Scoffin]

I would like to take 9 year old DD away on holiday for a few days in August, just me and her.
We did this type of holiday in Broadstairs a couple of years ago and it was lovely but we would like to try somewhere different this time.
We live in London and I don't drive which is the main limiting factor. It needs to be within say 2.5 hours of London by train and then we need to be able to get around by walking /public transport.
We will want easy access to the countryside (or maybe seaside) but also some nice places to eat, coffee shops etc and things to do if the weather is bad.
Hopefully not overwhelmed by tourists though that may be tricky in August.
Will probably stay in a B&B, fairly flexible on budget.
Would love any ideas, thank you!

Over your 2.5 hours but you could get direct train to Edinburgh from London, 4.5 hours. Loads there for kids: the castle, camera obscura, museum, the festival will be on too, can head to portobello beach. Bus services there are good so could stay a bit further out if city accommodation prices were crazy prices.

Will be a lot of tourists though so that suggestion fails your criteria there too sorry!

Rye is a wonderful place to stay, with the sand dunes at Camber Sands also accessible by public transport.

Exmouth is nice, maybe slightly further but lots to do including nearby towns and Exeter.

Rye is nice but very hilly and you’re reliant on buses if you don’t drive.

Dorset?

Deal is really nice and ticks a lot of those boxes.

York? Loads to do and near some fab countryside, or you can get the train to Scarborough for a beach day.

(The youth hostel in York is lovely and you could get a private room).

Thank you! Looking at all these suggestions. I think York could work well.

Im in a similar sit OP but with 2 DC.

No beaches but we had a really good weekend in Bath - stayed just outside in a lovely self catering which was effectively in the countryside. Very easy to get around the city on buses etc ( I even had a buggy at the time). Was very easy to jump on a bus into the city.

York also great as lots to do ( and agree the youth hostel is nice).

Also did west wittering and Chichester, which if you get the weather can be lovely.

If you want to do Edinburgh then North Berwick nice to stay in - but a long journey from London.

Brighton can be fun as well, but crowded. Another option I’ve done is Isle of Wight - which if you base yourself right can be done without a car, lots of laces you can stay and walk to things, but also a very good bus service. Getting the ferry is also quite fun.

We haven’t tried Broadstairs as I’d thought I’d need a car but think will take a look!

Hope you find somewhere and have a fab time.