It's party time for music lovers as the 20th T in the Park finally gets under way.

The first fans have arrived on site and organisers expect to welcome a record 35,000 campers to the festival today. This year's T headliners are Rhianna, Mumford and Sons and The Killers.

Temperatures are set to reach up to 27 degrees centigrade during the three-day festival, making a refreshing change from previous years when mud and rain has been the order of the day.

Festival Director Geoff Ellis, who gave the first 20 fans to enter the campsite today a VIP upgrade in celebration of T in the Park's 20th year, said: "Welcoming the first campers through the gates is my favourite moment of the festival every year. There was a phenomenal atmosphere today, and a great sense of excitement amongst the campers.

"As it's our 20th year, we wanted to do something special so giving 20 lucky ticket holders a VIP upgrade seemed like a good idea. The sun is shining, and it's been a glorious start to our 20th year festivities. We hope everyone has a fantastic weekend, and we can't wait to celebrate the 20th year of T in the Park with the fans, who truly are the greatest audience in the world."

The festival officially kicks off tomorrow, with crowds of 85,000 expected to attend each day to watch acts including Calvin Harris, Kraftwerk, Snoop Dogg, Emeli Sande, alt-J and the Yeah, Yeah, Yeahs.

However, Sub Club residents Harri and Domenic will lead a top line-up of DJs getting the party started tonight in the Slam Tent. Thursday campers will also get the first look at Arcadia's Afterburner, a fire and light pulsating structure which is set to become the hottest after-party destination for festival-goers.

George Kyle, Head of sponsorship, Tennent's Lager, said: "T in the Park is the best weekend of the year for us, and we're incredibly proud to have been the T in T in the Park since the very beginning. From all of us at Tennent's, we hope you all have a brilliant weekend. Here's to 20 great years."

Tickets for the festival are still available from the T in the Park website.

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