Easy access to different necessities of daily life makes a city more livable. This has motivated urban planning researchers to quantify urban accessibility from official city data. However, due to the manual nature of data collection, these earlier survey based analyses were limited in scope and scalability, and mostly offered insights on cities of developed countries like the UK and the USA. Using Google Places data that is crowd-sourced around the world, this paper gathers walkability information for twenty-five cities across five continents. We detail the collection methodology of this unprecedented dataset and show useful applications of this data in urban analysis: e.g., how different areas within a city compare against each other in terms of accessibility and which areas in a city would benefit the most from the least intervention.