The series is comprised of archived captures of websites and social media sites related to the October 1, 2017 mass shooting that occurred at the Route 91 Harvest Festival in Las Vegas, Nevada. UNLV Libraries Special Collections and Archives staff selected websites that represent immediate news coverage of the event from established and alternative news media. The majority of content on these sites is comprised of articles and news stories from local, national, and international news media outlets. Established news media sources include the Las Vegas Review-Journal, Las Vegas Sun, Fox News, The New York Times, and CNN. Alternative news media sources include the Las Vegas Weekly, Buzzfeed, and Truthfeed News. Websites and social media sites were also selected based on the most frequently shared URLs on Twitter related to the shooting in Las Vegas. The websites in this collection were crawled and captured using Archive-It from October 2017 to October 2018.