Where can you sit quietly without having to buy something?

Finding a seat away from home often comes with an expectation to order a drink or keep moving. Libraries, parks and community spaces can offer alternatives, but opening hours, toilets, weather and accessibility make a difference. A quiet corner is only useful if people can actually reach it and feel comfortable staying. What makes a public space welcoming for a short pause? General suggestions are welcome, especially features towns could provide more often. Please avoid identifying secluded places where someone regularly spends time alone.