The wall protects the billionaire's 700-acre Pilaa estate, which he bought in 2014 for about $120 million. Neighbors told Kauai's Garden Island newspaper that it's ugly and blocks their views.

Some of Facebook CEO Mark Zuckerberg’s neighbors are grumbling about a rock wall he’s having built on his property on the north shore of Kauai.

KILAUEA, KAUAI — For years, Kilauea, Kauai resident Gy Hall has enjoyed the view of the ocean and the breeze along Koolau Road. Then, a few weeks ago, a crew started to build a wall which ...