Aden Flint says it was a difficult decision to swap Swindon for Bristol City but admits the time was right to move on.
The centre back signed a four-year contract after passing a medical at Ashton Gate on Tuesday and believes it was the correct move for his career.
"It wasn't an easy decision, but I feel it is a massive opportunity for me to move forward in my career and improve as a player," he told the Swindon Advertiser.
"I want to say thanks to Swindon for giving me the chance to start in the professional game, and I will always be grateful, but the opportunity to sign for Bristol was too good to turn down.
"They have a massive chance of getting promoted back to the Championship next year, and it will be good to get another year in League One under my belt this year with Bristol, and then hopefully get up to the Championship for next season."