This legendary Portland shop is the world's largest used bookstore - the jewel in the crown of what is claimed to be the largest independent chain of bookstores on the planet. Powell's even provides a map for customers. "It is amazing. It is a whole city block with several floors of books. Unlike ordinary bookstores, Powell's has a huge selection of every book imaginable. I took my retired English teacher father there and he went crazy. It also has a cafe and a selection of antique computers. It is an absolute paradise for bibliophiles," says a reader.

Venice, Italy

In Acqua Alta (Italian for "high water"), boats, gondolas and canoes act as shelves of sorts for new and used books. "A mix of new and second-hand books jumbled over every surface and up every wall, and occasionally turned into part of the furniture, including a staircase of ancient encyclopedias that provides views over the canal at the rear. And when that rises and floods the shop, at least the books in the retired gondola will be saved," says a reader.

Buenos Aires, Argentina

An old theatre turned into a bookshop in downtown Buenos Aires, El Ateneo still keeps much of its former grandeur. Designed in 1919 by architects Peró and Torres Armengol, and turned into a bookshop 81 years later, readers can still see the high painted ceilings, balconies, carvings and even the theatre curtain. "Inside El Ateneo clients are respectfully quiet, just like an audience right before the start of a show. Sit in the cafe, order a , leaf through a Buenos Aires city guide and enjoy the majestic uniqueness of this book haven," says a reader. The stage is used as a reading area and cafe, with the former theatre boxes available as tiny reading rooms.

San Francisco, US

A destination in its own right for any visitor to San Francisco, City Lights was founded in 1953 by poet Lawrence Ferlinghetti and Peter D. Martin, and it was not only a place of congregation for authors of the Beat Generation, but also featured in many of their works. The first all-paperback bookshop in the US, City Lights has always published as well as sold, a tradition it maintains to this day with more than 20 new titles published each year. You can also pop across the street to Vesuvio Cafe where Kerouac, Ginsberg and Co used to hang out.

Paris, France

readers' most-nominated bookshop by far, Shakespeare and Co has it all: an amazing array of literature, a great programme of events, a sense of community and a great history. According to Jen Campbell, author of , Shakespeare and Co "embodies everything a bookshop should be". This little English bookshop on the left bank of the Seine, opposite Notre Dame, was opened by American George Whitman: "I created this bookstore like a man would write a novel, building each room like a chapter, and I like people to open the door the way they open a book, a book that leads into a magic world in their imaginations." But its inspiration was to honour Sylvia Beach, another American bookseller who had run a store with the same name in 1919 ("a gathering place for the great expat writers of the time - Joyce, Hemingway, Stein, Fitzgerald, Eliot, Pound - as well as for leading French writers", according to the website ). She was forced to close it during the second world war.

New York, US

It's almost a crime to visit the Big Apple without stopping at this magnificent independent bookstore next to Union Square. With exquisitely curated aisles and shelves, a great selection of both new and incredibly random second-hand bargains, rarities and collectibles, and a wonderful programme of events, this is a New York institution to treasure.

Minneapolis, US

This recommendation might not be everyone's cup of tea, but author Jen Campbell is clearly an enthusiast: "Wild Rumpus is filled with books ... and animals. Tilly and Pip are two little rats who live under the floorboards in a glass cage, so you can watch them running around. There are also two chinchillas, Amelia and Mr Skeeter; two ferrets, Doodle and Ferdinand; three cats, two doves, three cockatiels, two chickens, a lizard called Spike and a tarantula that goes by the name of Thomas Jefferson. Oh, and the bookshop door has a purple, child-sized door built into it, so children can let themselves in."

Bath, UK

This indie bookshop in central Bath not only has a great selection of books, a cosy atmosphere and comfy armchairs - it also offers services such as bibliotherapy and "reading spas", during which staff engage in one-on-one conversations with readers over a mug of coffee and recommend books they think are especially suited to that person.

Somewhere on the London canals

If you're not quick, you might miss this one. We were delighted when this book barge stopped for a while next to the office. Since Paddy Screech quit his former job in 2011, this floating store has been around London's Regent's canal - mostly next to Paddington station. Don't be put off by its seemingly small size (it can't be that small - it's also his home!) - there's a wide variety of books on sale inside, as well as cats and excellent music. They recently announced that they have been offered to take up permanent residence next to Granary Square, in King's Cross. As Screech said: "It's a symbol of independence. Bookshops are culture, and independent bookshops aren't struggling because people don't want them - it's because of this mad property market. Beyond that, living on the water, below the city, is sane-making." But we shouldn't forget other book barges, of course, like the Book Barge, which floats near Lichfield.

In a similar vein to little free libraries, these mini-bookshops bring reading everywhere. Our readers stumbled across the folks from Arma de Instrucción Masiva ("weapon of mass instruction", a project of Argentinian artist Raul Lemesoff) in Argentina - and we hear they are now in Belgium. We're also fond of the book van of Tell a Story in Lisbon, Portugal, and the folks at Dylan Mobile Bookstore in Swansea, Wales, which stocks antiquarian and second-hand books.