It's been almost four years since our first post on Tumblr, and that first post was a quote. Since then we've shared hundreds of our favourite quotes about sustainable cities, compiling a list of our favourites over two years ago. Now it's time for another compilation! Take a look at our list below and let us know in the comments, which great city quotes have we left off?

1. "Urbanization has lured more people to bustling metropolises, but precious little thought has been given to what happens when these cities fail. Over time, the underlying systems and processes of civilization – from lead mining to offshore drilling to car commuting – slowly poison us. Power grids brown out, the climate heats up, and industrial accidents ravage ecosystems and cities alike. For all the famed cities with thousands of years of continuity – Paris, London, Cairo, Athens, Rome, Istanbul – most cities just stop."  Ben Paynter

2. "People here can't realize there are poor people in the world. They can't think about the needs of other people." Suburbia by Bill Owens

3. "Medium and small cities, those which nobody knows about, are going to grow faster in the future. Our century is about global cities." The Mayor of Istanbul

4. "What if we chose to live close enough to work and the grocery store that we didn't need gas at all? What if we chose to reject gas as a necessity, therefore placing the power back in our own hands? The only real freedom is freedom from want. Let's stop wanting gasoline." Sierra Elizabeth

5. "How do we slow down what matters the most and speed up what benefits change and progress? We don't want to impede progress, but we are seeking reconnection to ourselves, to each other, and with the world." John Maeda

6. "When creative people gather together, it attracts other young creative people. If you look at demographics, the downtown area is much younger than it was a few years ago. There's this competition that's good. It isn't about making art anymore. It's about making good art." Courtney Hammond

7. "In a future that portends stronger and more-frequent hurricanes striking North America's Atlantic coast, ferocious winds will pummel tall, unsteady structures. Some will topple, knocking down others. Like a gap in the forest when a giant tree falls, new growth will rush in. Gradually, the asphalt jungle will give way to a real one." Alan Weisman

8. "We're moving from a generation who gave little thought as to the built environment and accepted housing that was neither pleasant to look at, nor to live in or around, to a new century where there's a real desire for housing that's affordable, flexible, and places community at the heart of its thinking. For architects and the public it's an enticing prospect." Will Gompertz

9. "It's amazing how I'm able to ride around on a bike. People kind of see it's me but since I'm on a bike, they think, 'No, it's not her.' And by the time they realize it's me, I'm already gone." Beyoncé

10. "We need more insurgency in the city in order to break unsustainable and privatizing patterns of urban development." Jeffrey Hou

11. "My laptop knows the exact location of every file and folder on its hard drive. It's barbaric that my house doesn't have a similar inventory of its contents." Tom Maly

12. "The banning of bullfighting in Catalonia was controversial and hard won and has now been replaced by the vacuous global consumption of the mall. I'm sure that is an advance for the bulls but I'm not sure how well it bodes for the serious business of being a city." Edwin Heathcote

13. "Food production and the food system must assume a much higher priority in political agendas across the world. To address the unprecedented challenges that lie ahead the food system needs to change more radically in the coming decades than ever before, including during the Industrial and Green Revolutions." Foresight: The Future of Food and Farming

14. "I'm not a big fan of capitalism or business, but it's pretty obvious that if we build a beautiful system of bike boulevards, bicyclists will come to ride them by the tens of thousands. When they do, they spend a lot of money and keep a lot of our local economy going." Chris Carlsson

15. "This has been quite simply a case study in exactly how not to upgrade a Tube line." Caroline Pidgeon

16. "Typically we don't think of cities as being particularly extreme environments, but few places on earth get as hot as a rooftop or as dry as the corner of a heated living room." Adam Rogers

17. "Ordinary people often see concrete as an unpleasant, overbearing material. Gentle spaces are easy to achieve with wood, but it's a real display of skill to design a comfortable home in concrete." Kazunori Fujimoto

18. "Any advert in a public space that gives you no choice whether you see it or not is yours. It's yours to take, re-arrange and re-use. You can do whatever you like with it. Asking for permission is like asking to keep a rock someone just threw at your head. You owe the companies nothing. Less than nothing, you especially don't owe them any courtesy. They owe you. They have re-arranged the world to put themselves in front of you. They never asked for your permission, don't even start asking for theirs." Banksy

19. "The second mode [to deal with unsafe cities] is to take refuge in vehicles. This is the technique practiced in the big wild-animal reservations of Africa, where tourists are warned to leave their cars under no circumstances until they reach a lodge. It is also the technique practiced in Los Angeles." Jane Jacobs

20. "There is a need for debate on what to do about slums or, to use the more polite term, informal settlements, in Africa given the current rates of urbanisation and population growth which are unprecedented in human history anywhere in this world. Slums always accompany the process of urbanisation. It is generally estimated by many economists that more than half the world's people now live in "slum" area of cities and work in the informal economy." Gilbert Nii-Okai Addy

Image via lightsurgery