"It's the first time I've seen a sign up," said hiker Shaun Peck.
"Nobody in the neighborhood has ever said anything," said hiker Robin West.
Now, there's a chain-cutting through the entrance and a flapping plastic sign that warns hikers are entering private property and that violators will be prosecuted.
"I've been hiking since little kid. I don't understand why put up a sign," said Peck.
Around a hundred hike the trail every day and thousands hike it every month.
Tourists and locals alike say they all know about it.
"They advertised it in Japanese magazine," said Henry Ng, who was visiting from Canada.
"The trail's in every guidebook. It's a popular trail," said Peck.
"So, the signs didn't deter you at all," asked KITV reporter Lara Yamada.
"It did a little bit, but we drove around for a while, asked a round, and they all said it was pretty safe," said Ng.
Even former Honolulu mayor Peter Carlisle said it's part of his routine.
"That's a remarkable view up there," he said.
Carlisle lives in Mariner's Ridge and said increasingly bad behavior by hikers had residents wanting landowner Kamehameha schools to do more to keep out the riff-raff.
"If someone's got a nice lawn and people rub dirty feet that's not right, and then there are the dangers such as lighting fires in the middle of the night," a problem Carlisle said he witnesses on a regular basis.
Kamehameha Schools told KITV the school has always warned visitors it's private property, but have never arrested anyone, issued a violation, or fine.
"This is something that can ultimately be resolved, but it will take a lot of heads together to see what needs to be done," said Carlisle.
In a statement, Kamehameha Schools spokesperson Kekoa Paulsen told KITV:
"We do not allow or encourage public access to the portions of the Kaluanui trail on Kamehameha Schools' land. This is not a public trail. Signs to this effect have been posted at the trail head for years, and a chain barricade was erected last year to further reinforce this message. There is no parking, sanitation or other basic infrastructure to support public use of this property. Neighbors have complained for years about trail users who block driveways, use water hoses without asking, leave their trash on the trail and in their yards, make loud noises when they arrive and leave, refuse to pick up after their dogs and, in some cases, have threatened neighbors who have taken it upon themselves to address the disrespectful behavior. For these and other reasons the Kaluanui trail is not open for public use."
City Parks Administrator Curt Cottrell also told KITV, because the property is part of a natural resource, the property owner must provide public access, similar to required beach access, but residents pressed the school to do more.