On the anniversary of one of the largest terrorist attacks on US soil, former NSA contractor and whistle blower Edward Snowden will discuss the status of the surveillance state with Jeremy Scahill, investigative journalist, author and co-founder of the online journal The Intercept. (Snowden will appear via closed-circuit TV from an undisclosed location.)

Where: Parkway Central Library at 1901 Vine St. 19103 When: September 11, 2017 at 7:30 p.m. How much: $15