Jenkins left the region at the end of last season to join RC Toulon in the south of France. The double British and Irish Lions prop first joined Cardiff Blues in 2004 and will link up with fellow Lion, hooker, Matthew Rees, who has also signed for the capital region.
Having started his rugby career at Beddau RFC, Gethin moved on to Pontypridd and then Celtic Warriors making his Wales debut against Romania in Wrexham in 2003.
Gethin played in all 10 Grand Slam games in 2005 and 2008 and also featured in every game of the 2003 and 2007 World Cups. A versatile prop who can play on either side of the scrum, Gethin became a national hero in Wales when his charge down try against Ireland at the Millennium Stadium in 2005 secured the Grand Slam for Wales for the first time for over 20 years.
Speaking of the signing Cardiff Blues Director of Rugby Phil Davies said,
"I am really pleased to have re-signed Gethin.
"We started the year knowing we had a young squad and it has been a massive season of progression, sometimes the results have not gone our way.
"Gethin will be coming back to an environment that is a little different from the one he left and I think, hopefully, he will enjoy it and I know that he will add a massive amount to the group.
"I have heard how professional he is and I am really looking forward to working with him and welcoming him back to the Blues.
"Gethin's experience will add to the team, he is very vocal on the pitch and I am sure that a lot of the youngsters will also be very vocal with him as well next year.
"The experience of Gethin, Matthew Rees along with the likes of Gavin Evans and Dafydd Hewitt who are really experienced players will help.
"Hopefully with the youthful exuberance of the young players combined with the experienced players will be an excellent mix for us next year.
"Gethin is an international player, a Lion and a quality player.
"I am delighted that he has come back, it is a fantastic signing for us.
"It is great to be able to bring a senior Wales player back.
"It was not an easy signing at times but to be fair to Richard Holland and Peter Thomas, they both worked exceptionally hard at it.
"I was keen for it to happen and to be fair they have done that, so credit to them.
Cardiff Blues CEO, Richard Holland, added,
"Gethin is undoubtedly a quality player having played for Wales for a decade and toured with the Lions twice.
"A lot of hard work has gone on behind the scenes to bring Gethin back to Wales and we are delighted that he has signed with the Cardiff Blues.
"As well as signing experienced players such as Gethin and Matthew Rees we have also signed key youngsters that we will build the team around for the future.
"Gethin will add a great deal of experience to our pack and I'm sure he will be looking forward to pairing up with fellow Lion, Matthew Rees, in the front row."
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