New York City will be the first city in the US to require proof of vaccination to enter a variety of indoor places, the city’s mayor announced yesterday. Mayor Bill de Blasio told a press conference that starting September 13, the city will start requiring the proof at indoor venues like bars, restaurants, and gyms. The so-called Key to NYC Pass (which, rather confusingly, is a program, not an actual pass) is part of a suite of efforts to fight the more-transmissible delta variant, as cases rise across the city. About 66% of the city’s adults are fully vaccinated, and officials hope the new requirements will convince more people to get the shots. The announcement follows the CDC’s new indoor mask guidance for places with substantial or high transmission, which has included New York in recent days.