William Walker, 44, was sentenced to 24 to 60 years in prison on Monday.
According to the Philadelphia district attorney's office, Walker raped the first victim in July, 2012 inside an assisted living facility. Investigators say he held the victim down with a pillow over her face.
Walker attacked the second victim just two blocks away, also at an assisted living facility. Investigators say he beat the woman over the head, dragged her into a wooded area and raped her.
The next day, investigators say Walker came upon the third victim on the street. He also dragged this woman into a wooded area, beat her and raped her.
Walker was caught one week later when a witness saw Walker dragging a woman down the street. The witness called 911 and police interrupted the assault.
Walker pleaded guilty to four counts of rape, one count of Aggravated Assault, two counts of simple assault and one count of Terroristic Threats.
The district attorney's office also noted the court already found him to be a Sexually Violent Predator under Pennsylvania's Megan's Law.