Metro Extracts are chunks of OpenStreetMap (OSM) data clipped to the rectangular region surrounding a particular city or region of interest. Data is available for locations around the world.
To download the OSM data, go to the Metro Extracts download page at https://mapzen.com/data/metro-extracts/. The page has a web map and list of popular places that available for immediate download. You can also create a custom extract, which can take up to 30-60 minutes to be created and requires a free Mapzen developer account.
Learn more about using Metro Extracts by following this tutorial. You will download the extracted OSM data for a region and load the file into QGIS, which is a free, open-source desktop GIS application.