Waitangi is so packed that those wanting to be there busted through gates to drive across a farm, arriving through a back door.
Police are now on Wakelin Rd, south of Kerikeri, turning motorists around.
They were called after an earlier altercation between the farmer and groups of cars with drivers determined to beat the traffic chaos.
The Herald was told by one farmer that Google Maps shows the farm tracks as a through road even though it had never been open to the public.
The misleading route guidance - which the farmer said he had reported to Google repeatedly without success - told motorists they could turn off State Highway 10 down Wakelin Rd and arrive at a back entrance to Waitangi, near the popular mountain bike park.
As traffic built up - almost back to the Kerikeri roundabout at one stage - cars tried the Wakelin Rd route, opening gates and driving through the farm despite the farmer’s protestations.
Cars continue to attempt the route with about one every few minutes turning up to be told by police to turn around and go back.
One person told the Herald drivers have smashed through fences on their way through.
Residents fumed on a local Facebook page in response to the situation. “Super rude,” said one.
Earlier, there was a significant traffic backup from the Puketona Junction Roundabout to Haruru. The Advocate understands vehicles have been reported driving on the wrong side of the road to get past and performers due at Waitangi were stuck in queues.
At midday, traffic was still backed up for nearly 7km approaching the grounds according to Google Maps.
Earlier, police issued advice to those trying to head to the area.
“Those heading to celebrations at the Treaty Grounds today are asked to travel via Puketona, and take advantage of the parking and shuttle buses into Waitangi from Bledisloe Domain,” police said in a statement.
Amid increased tensions between the coalition Government and Māori, thousands of people gathered in the Bay of Islands this morning before dawn to commemorate the Treaty of Waitangi.
Political and community leaders offered prayers and readings to the crowd as the sun rose.
After 10am, the crowd was joined by a hīkoi in defence of Te Tiriti o Waitangi to its own chant of: “Two, four, six, eight, this government is out the gate”.
The march left Te Rēinga Wairua [Cape Reinga] at dawn on February 2 and reached Te Tii Marae this morning.