Rapper Lil' Kim has begun a 366-day prison sentence after she was convicted of perjury for trying to cover up two friends' involvement in a shooting.
The rap star was upbeat starting her jail term, said her lawyer
The star was taken to Philadelphia federal detention centre at about 1645 local time (2145 BST) on Monday.
"She was upbeat and smiling," said her lawyer, L Londell McMillan.
The 30-year-old was convicted in March of lying to a grand jury by claiming two men were not at the scene of a 2001 gun battle in New York.
Ex-manager Damion Butler and former bodyguard Suif Jackson have both since pleaded guilty to gun charges.
On Monday, Lil' Kim - real name Kimberly Jones - arrived in Philadelphia with a entourage of 20 to 25 people, say reports.
She was accompanied into the prison by her mother, brother and lawyer.
"She told her mom not to cry and to stay strong," said Mr McMillan.
Earlier, the musician issued a statement in which she said: "Today begins a new saga in my life which I expect to strengthen me and allow me time for reflection.
"I plan to write music while in prison, read and pray regularly and will come out a stronger, more confident woman."
The 4ft 11in (1.5 metre) music star also criticised the decision to send her to the concrete, high-rise facility in Philadelphia rather than a prison camp "as discussed".
"I am not certain that this constitutes fair and equal treatment," she said.
Jones claimed Butler was not at the station and denied knowing Jackson
Her lawyer said the celebrity would be in danger in the detention centre and that he was seeking to have her moved.
She could be released in nine months' time for good behaviour.
"Why should a female hip-hop artist have to spend time in an urban concrete jungle while other female prisoners are assigned to rural, suburban-type prison camps?" he said.
Charges were brought against her after a gunfight erupted outside the Hot 97 radio station in 2001 as a rival rap group was arriving.
The rapper, and members of her rap group Junior Mafia, had been guests on the station.
As they left the building, a shootout broke out between members of her entourage and rival group Capone-N-Noreaga. One man was injured.
The group had challenged their rivals about an insult aimed at Jones by another female rapper, Foxy Brown, in a song called Bang Bang.
Jones was accused of lying numerous times in 2003 court appearances when she told a grand jury Damion Butler was not at the station on the day and denied knowing Suif Jackson.
Jurors at her trial were shown security images which showed Butler opening a door for the rapper, while two witnesses, who once made records with her, said they saw her at the station with both men.
Jones won a Grammy in 2001 for her part in the hit remake of Lady Marmalade alongside singers Christina Aguilera, Pink and Mya.