The City of Philadelphia will allow 50% capacity May 21 and 100% capacity June 11
Baseball fans return for 2021 MLB season: Every team's Opening Day plan for in-person attendance
Jack Coombs Field Facility Page and A-Z Game Day Guide - Duke University
MLB opening day 2021 brings hope as normalcy slowly returns
Baseball fans return for 2021 MLB season: Every team's Opening Day plan for in-person attendance
Maryland governor lifts capacity restrictions; Orioles plan for fans in the stands - Ballpark Digest
Orlando major league baseball stadium proposed
MLSE removing proof of vaccination requirement at all events starting March 1
Kyrie Irving, Unvaccinated Yankees and Mets Can Play at Home as NYC to Lift Mandate: Sources – NBC New York
Ontario health official would consider lifting capacity limits in venues with coronavirus vaccination requirements
Coronavirus outbreak: Live updates on COVID-19
Camden Yards allowed up to 50 percent attendance, per governor's order - The Washington Post
Capacity limits lifted in MLB ballparks