On a city lake at night, a dozen glowing robot swans glide across the water in a synchronised dance. The artwork CYGNUS by Berlin-based duo Loomaland is a bizarre and beautiful sight at Adelaide's Rymill Park Lake, as part of the Illuminate Adelaide festival. The city's winter celebration of art, light, music and technology was first staged in 2021 and attracted an audience of about 500,000 people. That's now grown to more than 1.5 million, thanks to a crowd-pleasing program of mostly free events.