Supporters wore "Make America Great Again" hats while members of the United Steelworkers union came out to protest.
Trump supporters yelled "Bye, Felicia" when anti-Trump protesters were drowned out by a semi horn.
The Republican presidential nominee entered his rally waving a Terrible Towel, with "Proud to be an American" playing in the background.
It's been a busy few days for Trump. Here's the 101 on his rally at Ambridge Area High School.