Visit a museum for free (thanks to Wawa and PECO)

What As part of the Welcome America fest, some museums are waiving admission fees. Saturday it's the National Constitution Center; Sunday it's the Barnes and the Art Museum (well, that one's pay what you wish).
Where Several museums at various addresses around Philly
When July 2, 2016 at 9:00 am to July 3, 2016 at 5:00 pm
How much Free