From a distance, the two cannons look like odd-shaped rocks in the salt water.

In fact, that's what Mike Petrone took them to be. However, his 12-year-old daughter Miranda noticed something unusual.

"We were looking at stumps and we saw this cool rock and ... she said, 'No, there's rust on it,' " Petrone told KGW.

Heavy surf washed up the two cannons on the Oregon coast last Saturday near Arch Cape, just south of Cannon Beach, and the discovery is garnering wide-spread attention.

Officials believe the twin cannons could be from the U.S.S. Shark, a survey schooner that sank in the Columbia River Bar in 1846.

When one of the cannons washed ashore shortly after the schooner sank, coastal residents named the area Cannon Beach.

"It's tremendously exciting to see Oregon's past pay us a visit ... It's important for people to visit the shore and see the artifacts, but in a way that protects your safety and preserves the integrity of the artifacts," said Chris Havel, spokesman for the Oregon Parks and Recreation Department.

The cannons are visible at low tide.

"This could very well be an important historic site. Moving, touching, or taking parts of the cannon instantly destroys historical information that could help us understand where the cannons are from and what they mean to Oregon history," Havel said.

Historians and archaeologists are devising a plan to protect the important artifacts and study the broader area. They hope to move the cannons to a safer place later this week.

The U.S.S. Shark was the first U.S. war vessel to pass through the Straits of Magellan from east to west.

If the cannons are from the Shark, they'll likely go on display in a town museum.