Work is being done around the clock to install 90,000 solar powered LED lights on the Auckland Harbour Bridge.
Lines company Vector is paying for the $10 million project in a bid to better showcase the landmark.
Project manager Paul Cannin said planning started early last year with construction beginning in August.
"For Vector it's an opportunity, it's not just about the lights on the bridge, we've also installed a large solar panel down at Wynyard Quarter with a large scale utility battery so it's about showcasing new technology as well.
"These lights are going to be powered by the solar energy we collect during the day, so there will be no power bill," Mr Cannin said.
He said the lights can go any colour of the rainbow and can be programmed into patterns to go with music.
"I think it's going to look spectacular, it's going to change the Auckland skyline, people are going to wonder why we didn't do this earlier.
"It's going to be lit up in an architectural setting every night of the year then there will be about 20 events a year where we will put on an artistic display."
Mandylights are in charge of installing the lights - it also installed lights on the Sydney Harbour Bridge
Project manager JP Jammaers said the LED strips were being installed along every beam and the arch of the bridge, and others will light up the pillars underneath.
"We've had to abseil to get to some parts of the bridge, it's not a straightforward job.
"The bridge poses so many challenges.
"The environment is probably one of the harshest environments you can put anything, we are constantly battered by all sorts of weather, plus you have the salt water air which corrodes things within days if they're not protected," he said.
Some tests have already been carried out with the lights set to be switched on on Auckland anniversary weekend at the end of the month.