The Baggins Book Bazaar in Rochester is a second hand book shop and then some!
The Largest Secondhand Bookshop in England
Baggins Book Bazaar is a purveyor of secondhand books located in the historic city of Rochester, Kent. With a large range of titles appealing to all tastes and ages, set out in labyrinthine rows of books, there is something here for everyone. Any visit to Rochester would be incomplete without a browse around Baggins.
From their website

It’s incredibly cheerful and welcoming. There are books piled all over from floor to ceiling (shelves…for the most part!) – but still in alphabetical and subject order.
It’s the sort of chaos that would drive me crazy to work in, but fills me with delight to browse through.
And it’s huge!

Best of all, the bookseller was able to direct me to the ‘new’ shelves at the front, once he saw what I was searching for! Three floors and he knew exactly where the books I wanted were!
A must visit when in Rochester.