Ancient rock carvings have been discovered on a beach in Hawaii.

Shifting sands on Waianae coast in the island of Oahu in Hawaii have revealed petroglyphs that are believed to be 400 years old, officials from Hawaii's Department of Land and Natural Resources said.

A couple from Texas who happened to discover the petroglyphs by accident in July said that they noticed the carvings when a beam of light had shone on one of them. The couple discovered a petroglyph that had been etched into the sandstone hundreds of years ago, CNN reports.

According to the U.S. Army archaeology team, which manages many of the archaeological sites in Hawaii, 17 carvings have been found in the sandstone shoreline, with one that measures almost 5 feet long. Most of the carvings were of human figures and some even included carvings of the figures' fingers.

Alton Exzabe, an archaeologist for the U.S. Army, said that carvings showing fingers and hands are unusual. Moreover, most petroglyphs are only about a foot tall, but the recently discovered carvings on Waianae are bigger.

"What's interesting is the Army in Hawaii manages several thousand archaeological sites, but this is the first one with petroglyphs directly on the shoreline," Exzabe told CNN.

"What's exciting for me is I grew up coming to this beach and now as an archaeologist working for the Army, helping to manage this site, we discovered these petroglyphs that have never been recorded. Some people have said they've seen them before, but this is quite a significant find."

According to Glen Kila, a lineal descendant of aboriginal families who live in the Waianae coast said that the petroglyphs record their genealogy and religion.

"It's very important to know about the lineal descendants of the area and their understanding of these petroglyphs," Kila said.

Hawaii's Department of Land and Natural Resources has just started their plan of preserving petroglyphs. According to archaeologists, petroglyphs are extremely fragile, even the slight brushing of sand can damage them.

The Hawaiian islands are home to a number of petroglyph sites, including the famous Pu'u Loa petroglyphs at Volcanoes National Park. According to Live Science, aboriginal people used to make petroglyphs to record travelers' passage, and buried newborn babies' umbilical cord for long life.