  Sidewalks play a pivotal role in urban mobility of everyday life. Ideally,
sidewalks provide a safe walkway for pedestrians, link public transportation
facilities, and equip people with routing and navigation services. However,
there is a scarcity of open sidewalk data, which not only impacts the
accessibility and walkability of cities but also limits policymakers in
generating insightful measures to improve the current state of pedestrian
facilities. As one of the most famous crowdsourced data repositories,
OpenStreetMap (OSM) could aid the lack of open sidewalk data to a large extent.
However, completeness and quality of OSM data have long been a major issue. In
this paper, we offer a preliminary study on the availability and
trustworthiness of OSM sidewalk data. First, we compare OSM sidewalk data
coverage in over 50 major cities in the United States. Then, we select three
major cities (Seattle, Chicago, and New York City) to further analyze the
completeness of sidewalk data and its features, and to compute a
trustworthiness index leveraging historical OSM sidewalk data.
