Thousands are expected to gather to see some of the world's top triathletes competing this weekend for the Barfoot & Thompson World Triathlon series which runs until Labour Day.
Daryl McIntosh from Auckland Transport told the Herald people coming into the city for the event or other attractions in the area should plan their journey and be aware of road closures. There will also be parking restrictions and bus changes and a number of bus stops in the central city will be temporarily relocated.
Main roads affected in the CBD include Queen St, Albert St, Quay St, The Strand, Victoria St and Wellesley St.
It's recommended that people travel to the event by bus, train or ferry.
Triathlon NZ chief executive Craig Waugh said it was an exciting time for the sport, which has attracted 160,000 people from all over the country in the past 12 months.
"From a recreational point of view, it's a good Kiwi sport to get into - people love to bike, run and swim. It's also got a clean, green vibe to it," Mr Waugh said.
About 3000 people are expected to compete in the triathlon series - including 750 New Zealanders.
In the women's elite event Andrea Hewitt, Kate McIlroy, Nicky Samuels and Debbie Tanner line up, while in the men's the Kiwi colours will be worn by Bevan Docherty, Kris Gemmell, Ryan Sissons and Clark Ellice.
"The sport is going crazy globally and we're riding that wave out here as well. It's very popular and it's the fastest-growing sport here at the moment," Mr Waugh said.
This weekend's event is the grand final of a seven-race series as part of the ITU World Triathlon Series, and will feature the world's best Olympic triathletes.
Based at Queens Wharf, the elite course features a 1500m swim, 40km bike and 10km run over a hilly coursed.
Along with the senior elite event for men and women, there are also U23 and junior elite divisions.
People are encouraged to arrive early for some of the best spots to watch the athletes: along Queen St, Shortland St, at the Queens Wharf grandstand and around The Cloud.
Sports & Lifestyle Expo - Queens Wharf
Sat 20 Oct: 7am - 3:5:3 Solo Tri
Sat 20 Oct: 9:15am - U23 Women
Sat 20 Oct: 12.16pm - Elite Women
Sat 20 Oct: 3.15pm - U23 Men
Sun 21 Oct: 7am - 3:5:3 Teams Tri
Sun 21 Oct: 11am - Junior Women
Sun 21 Oct: 1.06pm - Elite Men
Sun 21 Oct: 4pm - Junior Men
Mon 22 Oct: 6.55am - Age Group (Sprint Distance World Champs)
Mon 22 Oct: 8.30am - Age Group (Olympic Distance World Champs)
Mon 22 Oct: 3.15pm - Paratriathlon World Champs