The leaders of MIQ have paid tribute to a system they describe as a cornerstone of New Zealand's COVID-19 elimination strategy.
One year ago today, all arrivals at New Zealand airports began to be taken to managed isolation hotels for a 14-day stay.
Since then, 130,600 people have passed through the 32 border hotels.
Joint head Megan Main said staff working at the facilities had made "considerable personal sacrifices" to keep those people safe.
More than 850 people have tested positive for COVID-19 during their stay - including about 95 current cases.
Main said MIQ had been a process of continuous improvement and the biggest learning curve had been adapting "at pace".
"If something goes wrong, we get together and learn from it. If our operating environment needs changing, we work together with colleagues from the Ministry of Health in particular to look at new policies we need to introduce. Anything we need to do to strengthen infection prevention control. It's faced paced," she said.
"We've learnt as we've gone and we're in such a different position today from a year ago. I'm really proud of where we've got to. I'm proud of the people involved and I'm proud of what we've been able to do for New Zealand."
The Ministry of Business, Innovation and Employment alone has spent more than $450 million on the system to date. That excludes expenses incurred by the Ministry of Health prior to June 2020, and those of agencies like the police, Defence Force and Ministry of Health.
There are more than 4500 hotel rooms across five cities, served by more than 4000 staff.
They have delivered 9.1 million meals and snacks, and conducted more than 900 swabs each day.
Brigadier Jim Bliss said MIQ had grown into a "massive logistical exercise which runs incredibly smoothly and has served our country very well".
He said he wanted to acknowledge the resilience of returnees who had arrived from all over the globe - sometimes in "extremely difficult circumstances".
"They have had considerable restrictions on their movement and contact with the outside world, but they have stoically completed their 14 days of managed isolation and where necessary, quarantine. They have all played a really important part."
One year of MIQ: A timeline
February 6: New Zealand's first taste of quarantine. 193 evacuees arrive on an Air New Zealand flight from Wuhan. 23 carry on to Australia and the remainder are kept for two weeks at a military base in Whangaparaoa.
March 14: The government announces anyone entering the country will have to self-isolate for 14 days, except people arriving from the Pacific. Cruise ships are banned from the country. Prime Minister Jacinda Ardern later advises that any tourists who enter the country and don't self-isolate could be deported.
March 19: The government announces it will close the country's borders to everyone except New Zealand citizens and permanent residents.
March 20: An MIQ unit is created as part of the COVID-19 All-of-Government response.
March 24: Any international arrivals who indicate they have symptoms of COVID-19 are taken to a quarantine facility near Auckland Airport. Any other arrivals who don't have a suitable plan for self-isolation - or a way to get to their self-isolation within 5 hours drive of Auckland Airport -are put into managed isolation hotels.
April 9: Prime Minister Jacinda Ardern announces anyone coming into the country, who boards their flight after midnight that day, will have to go into managed isolation provided by the government. Up to 18 hotels in Auckland and Christchurch will be used.
June 17: Air Commodore Darryn Webb is appointed Head of Managed Isolation and Quarantine and Megan Woods given Ministerial responsibility.
Webb orders a full audit of the hotels, doubles the number of Defence Force staff helping to run them, and brings in exit testing, ensuring no one leaves a facility without a negative COVID-19 test.
This is in response to reports of returnees mixing and mingling in facilities and members of the public holding events in MIQ hotels.
June 21: MIQ is gradually expanding - with new facilities opening in Rotorua, then Christchurch, Hamilton and Auckland. By the end of the month there are 32 hotels.
June 28: The government releases a review of MIQ. MBIE says it's standardising procedures across the hotels. People breaching the rules will face a $4000 fine or six months in jail.
July 4: A woman climbs the fence of the Pullman Hotel in Auckland and escapes. She is caught several streets away, arrested and charged under the COVID-19 Public Health Response Act.
July 7: A man leaves the Stamford MIQ Hotel in Auckland and goes to the supermarket. He is charged under the COVID-19 Public Health Response Act, and the fencing at all MIQ facilities is upgraded to six-foot high barriers.
July 9: The government announces there will be a permanent police presence at every MIQ facility.
Meanwhile, a man cuts through a fence at the Distinction MIQ Hotel in Hamilton, escapes, visits a liquor store, and is arrested.
July 11: A person breaks a window at the Waipuna MIQ Hotel in Mt Wellington and escapes. They're caught an hour later and a security guard is stationed outside their room for the rest of their stay.
July 24: Four teenagers and a mother flee from the Distinction MIQ Hotel in Hamilton to try and attend their father's funeral. They're caught in a park about an hour later - the mother is subsequently given a two-week jail sentence.
July 30: A man flees the Crowne Plaza MIQ Hotel in Auckland and is caught up the road. He is charged under the COVID-19 Public Health Response Act.
August 11: A fees scheme is introduced. Returnees arriving for less than 90 days must pay $3100 per person, for an individual room - approximately half the total cost of their stay.
August 20: Authorities have a theory about how a maintenance worker caught COVID-19 in the Rydges Hotel at the end of July. It's believed the virus could have been transmitted via a lift button.
October 2: Authorities trace a recent COVID-19 infection back to a rubbish bin lid touched by two different MIQ guests in the Rydges MIQ Hotel in Auckland. From now, it's announced all bins in MIQ facilities will be no-touch, and all rubbish will have to be securely sealed.
October 5: An MIQ booking system is launched. Anyone entering New Zealand will need to book a place at a MIQ facility if they're arriving after 12am on November 3. The only exceptions are people who meet very strict emergency allocation criteria - i.e they have an imminent threat to their life or serious risk to their health.
December 4: More people now qualify for emergency allocation, with the criteria widened to include people visiting dying relatives, people who need to look after a dependent person in New Zealand, and some critical workers.
December 14: New Zealand Army Brigadier Jim Bliss is appointed the new head of Managed Isolation and Quarantine.
January 28: No new returnees will be sent to the Pullman MIQ Hotel in Auckland, as authorities investigate transmission of the virus between four guests.
January 19: A staff member at the Grand Millennium is dismissed after a 20 minute "bedroom encounter" with a returnee.
The 100,000th returnee arrives in MIQ.
February 20: MIQ workers begin to be vaccinated for COVID-19.
March 2: MIQ fees are increased by about $2000 for temporary visa holders.
March 23: People must now stay in New Zealand for at least 180 days to be exempt from MIQ fees.
April 1: It's now easier for people to travel to New Zealand urgently, and secure a place in MIQ without booking ahead. MBIE has widened the criteria for emergency allocation.
April 9: A security guard working at the Grand Millennium MIQ Hotel tests positive for COVID-19. Health authorities launch an audit of the hotel.