Hundreds of demonstrators have gathered at the base of Hawaii’s tallest mountain to protest against the construction of a giant telescope on land that some Native Hawaiians consider sacred.
State and local officials will try to close the road to the summit of Mauna Kea on Monday morning to allow trucks carrying construction equipment to make their way to the top.
Officials said anyone breaking the law will be prosecuted.
Protesters who blocked the road during previous attempts to begin construction have been arrested.
Scientists hope the massive telescope they planned for the site – a world-renowned location for astronomy – will help them peer back to the time just after the Big Bang and answer fundamental questions about the universe.
But some Native Hawaiians consider the land holy, as a realm of gods and a place of worship.
Groups of activists sang and prayed at the base of the mountain on Sunday afternoon.
They declared the area, which is well off the highway at the intersection of the mountain’s access road, a place of refuge and safety.
“This is Hawaiian homelands,” said Kealoha Pisciotta, one of the protest leaders.
“We’re clearly out of their way, we’re not obstructing anything, everyone is in ceremony.”
The project has already been delayed by years of legal battles and demonstrations, drawing attention from the likes of Aquaman actor Jason Momoa, who has Native Hawaiian ancestry and has voiced opposition to the telescope.
Scientists selected Mauna Kea in 2009 after a five-year, worldwide search for the ideal site.
Protests disrupted a groundbreaking and Hawaiian blessing ceremony at the site in 2014.
After that, the demonstrations intensified.
Construction stopped in April 2015 after protesters were arrested for blocking the work.
A second attempt to restart construction a few months later ended with more arrests and crews pulling back.
But Hawaii’s Supreme Court has ruled the construction is legal, permits are in place, and the state has given the company behind the telescope a green light to resume its efforts.
The company is made up of a group of universities in California and Canada, with partners from China, India and Japan.
According to the University of Hawaii, ancient Hawaiians considered the location kapu, or forbidden.
Only the highest-ranking chiefs and priests were allowed to make the long trek to Mauna Kea’s summit above the clouds.
Today, the university leases the land at the summit from the state for existing telescopes and observatories on the summit.
A road built for telescope access decades ago is used by thousands of tourists and locals each year, including Native Hawaiians who go there to pray.
Supporters of the 1.4 billion dollar giant telescope say the cutting-edge instrument will not only make important scientific discoveries but bring educational and economic opportunities to Hawaii.
The telescope’s primary mirror would measure 98ft (30 metres) in diameter.
It would be three times as wide as the world’s largest existing visible-light telescope, with nine times more area.
Governor David Ige said unarmed National Guard units will be used to transport personnel and supplies and enforce some road closures, but they will not be used in a law enforcement capacity during planned protests.
In a news conference, Mr Ige said that he “respected the right of people to protest” at the telescope site as long as protesters behave lawfully.
“As construction begins, our number one priority is keeping everyone safe,” Mr Ige said, adding that he wants to make sure construction workers and truck drivers have unimpeded access to the telescope site.