President and first lady hike Koko Crater Railway Trail

HONOLULU (HawaiiNewsNow) - President Barack Obama and the first lady took on the Koko Crater Railway Trail on Tuesday morning, greeting fellow hikers along the way.

Hikers were stunned to see the president on the trail, which has railway tracks that serve as steps to the summit. Total steps to the top? About 1,100.

Kehau Kimokeo, 25, was just making her way to the start of the trail when she saw police cars and big, black SUVs zooming into the parking lot. There were Secret Service agents "everywhere," she said. That's when she spotted the president and first lady.

Hikers were asked to wait at the bottom of the trail to let the president, his friends and a security detail go ahead. As he walked by hikers, he waved, gave the shaka and wished people a "Merry Christmas!"

Once Kimokeo got to the top of the trail, she saw the president again. "He was maybe eight feet away," she said. "It was amazing."

She snapped a selfie with him in the background. "He wasn't looking, but I was," she quipped.

Rika Ravichandran, 20, decided to go hiking Tuesday on a whim, rather than staying home. She hadn't been on the trail for over a year.

She said she was just heading down from the top of the trail when she spotted the president.

"I saw him walk by and I was like, 'Oh my gosh, that's the president,'" she said.

Ravichandran snapped a photo at the hike's lookout of the president, who was wearing a black t-shirt, track pants and a black ball cap, smiling and enjoying the view. She said it was a little surreal to see a larger-than life-figure sitting on a trail she knows well.

"It was really unexpected," she said.

Hikers also took to social media after seeing the president on the trail. One Twitter user said the president told her she was in shape.

This is the second hike the president has taken on since arriving in the islands on Saturday.

On Sunday, Obama, his family and friends spent a windy, rainy morning outdoors, hiking at the Makiki Loop Hawaii Nature Center.

The Obama family arrived in Honolulu around 2 a.m. Saturday, and is expected to stay for about two weeks, leaving on Jan. 3.

Mobile users: Click here to see a slideshow of the first family's 2015 Christmas vacation in Hawaii.

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