Before the 53-year-old learned his fate, he listened to the words of one of his victims. Michelle Knight talked about her ordeal of physical and mental torture as Castro's prisoner.
"The years turned into eternity. I knew nobody cared about me. He told me that my family didn't care," Knight described.
"I can forgive you but I will never forget. With the guidance of God, I will prevail and help others that's suffered at the hands of others. Writing this statement gave me the strength to be a stronger woman," she continued.
Knight was the only victim to testify. Relatives spoke for the other two victims.
Castro showed little emotion as Knight spoke. He also addressed the court for nearly half an hour during his sentencing hearing. He apologized to his victims but also claimed most of the sex was consensual.
Castro also said he isn't a monster, and that he is sick and addicted to pornography. He said he didn't even plan the first kidnapping.
He said he knows what he did was wrong, but that he's not a violent person and his captives asked for sex and weren't tortured.
Once Castro finished, Judge Michael Russo thanked Knight for showing "remarkable restraint" during his statement. The judge then dismissed Castro's claims that the women lived a happy life with him.
"I'm not sure there's anyone in America that would agree with you," he said.
The women described horrific conditions in the home, which Castro turned into a prison. It was just three months ago that Amanda Berry, Gina DeJesus and Knight managed to escape from Castro's Cleveland home.
Knight was the first woman abducted by Castro in 2002 after he lured her into his house with the promise of a puppy for her son. She said she spent 11 years in hell and that Castro's hell is now beginning.
Castro got the life term for the most serious count and was getting additional time for the hundreds of other counts. A plea deal struck last week spared him from a possible death sentence for beating and starving a pregnant victim until she miscarried.
He pleaded guilty to 937 counts of rape, kidnapping and aggravated murder. He held his three victims captive in his home for approximately 10 years, where he repeatedly raped and beat them. That house will be demolished.
The three women disappeared between 2002 and 2004. Berry gave birth to Castro's daughter while in captivity. At the sentencing hearing, Castro was prohibited from ever seeing that child.
The Associated Press contributed to this report.