More than 40,000 young adults have filled stadiums in Atlanta and Houston this weekend for three days of teaching and worship.

Passion 2016 attracted participants aged 18-25 from across the United States and from dozens of countries around the world.

For the first time since its foundation by Louie Giglio in 1997 the event was live-streamed, allowing attenders to experience teaching from two speakers live while seeing the others via live-stream. Each venue had live worship music in every session.

The event took place in Atlanta's Philips Arena and Infinite Energy Center, and in Houston's Toyota Center 800 miles away.

Among the speakers and worship leaders this year were Louie Giglio, Chris Tomlin, Crowder, Matt Redman, Christy Nockels, Kristian Stanfill, and Brett Younker, with special guests John Piper, Christine Caine, Ravi Zacharias, Hillsong United and Rend Collective.

Open the first session, Passion Conferences founder Louie Giglio said: "The invitation for everyone is to come and see what God has done. We will see that Jesus is alive. He is risen."

As well as worshiping, young people aimed to serve. Students filled bins with thousands of towels and socks – two of the most needed items at homeless shelters – upon arrival at Passion events. This year, Atlanta's City of Refuge and Houston's Star of Hope will receive the donated items.

"Any time a conference comes to a city, the city feels the effects – hotels and restaurants are affected," said Ben Stuart, host at Toyota Center. "But when a conference of Jesus followers comes to a city, they should also bring the love of Jesus in real and tangible ways, which is why we bring the towels and socks."

Additionally, in the past few years, students have given some $8 million to fight modern-day slavery through The END IT Movement, assisting in awareness, prevention, rescue and restoration. While ending modern-day slavery is still a focus of Passion 2016, this year students are also donating money for the construction of a hospital to serve at-risk mothers and children in war-torn Syria. Once completed, the hospital will offer the first neonatal intensive care unit in opposition-controlled Syria.