5 Seconds of Summer's Rock Out With Your Socks Out Tour kicked off Monday in Lisbon, Portugal!

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The Australian band was stoked for their tour to begin as they tweeted Monday morning, "It starts TODAY..."

Ashton Irwin, Luke Hemmings, Calum Hood and Michael Clifford's excitement continued to show as they tweeted later on in the day, "FIRST STOP! One night only! LISBON".

5 Seconds of Summer Performing At BBC Radio 1's Big Weekend On The Main Stage The drummer even called Lisbon "a beautiful city!"

The Aussies showed off their pre-show stretching since it's "important."

Clifford shared a snap of Hemmings with his "LLAMAS UP".

The band's drummer continued to share his love for Lisbon and all of Europe.

He said opening night of the tour "felt absolutely wonderful."

He also shared a photo of himself playing his drums.

One other photo the drummer shared was of the crowd.

He and his bandmates mentioned they premiered a new song called "Permanent Vacation" during the first night of their tour. He hopes fans "dig it!"

Hemmings said their show in Lisbon was "wonderful" and it was a "great start to the tour."

Hood insisted the tour had the "perfect start" and he has "fallen in love with Portugal."

Clifford called the opening night of tour "amazing."

It certainly seems like their headlining tour is off to an excellent start!