
A view of the light show and festivities in the public plaza.

A group of children stand in awe of the multi-colored lights projecting onto the Medical Center.

The audience gets excited as the light show begins on new medical center complex.

Singer Michael Franti invited patients to join him on stage during his performance. He explained to the crowd that the event had special significance to him because his own 15-year-old son had been a long-term patient at UCSF.

UCSF Medical Center CEO Mark Laret pauses for a selfie with San Francisco Giants home run king Barry Bonds, a longtime supporter of the UCSF Benioff Children's Hospital.

Gjelina Abrenico, 3, helps paint a mural during the Lights On Festival.

Kenna Stuck, who received a life-saving bone marrow transplant as part of her cancer treatment at UCSF, returned with her parents, Doug and Kelly, to support the new hospitals. Read more about Kenna's story here.

An acrobat hovers over the crowd during the Lights On Festival outside the new medical center complex.

Brian McEnnerney, who led the fundraising team Brian's VIPs to thank UCSF Medical Center for the care he received last summer, poses with jewelry designer and philanthropist Jennifer Montana at the Lights On Festival.

Costumed stilt walkers cheered people along the Hard Hat Walk route.

Superhero Teddy Reibel, 5, whose older sister Rosalie was treated for brain cancer at UCSF, soared past AT&T Park during the Hard Hat Walk.

The relaxed 5K walk followed the waterfront, around AT&T Park and back through the Mission Bay neighborhood.

The UCSF Cancer Crusaders was one of many teams that dressed in fun costumes for the event.

UCSF Chancellor Sam Hawgood, MBBS, leads the pack for the Hard Hat Walk, joined by Olympic champion figure skater Kristi Yamaguchi (right).

Thousands gather at the start line of the Hard Hat Walk, getting ready for a 5K walk through the Mission Bay neighborhood.

Nilani, a facility dog at UCSF Benioff Children's Hospital San Francisco, leads her own team at the Hard Hat Walk.

Saleh Adi, MD, director of the UCSF Madison Clinic for Pediatric Diabetes, takes on the ALS Ice Bucket Challenge while supporting the new hospitals. He gave the honor of dousing him to the two top fundraisers on the Madison Clinic team, nurses Jeanne Buchanan (left) and Lauren Horton (right).

Sheena Fitzpatrick, a front desk supervisor at the UCSF Helen Diller Comprehensive Cancer Center, dons a special hard hat for the 5K walk.

Jugglers and other circus performers entertained attendees of all ages during the Hard Hat Walk.