Nine Sisters facts for kids

The view from the top of Bishop Peak looking towards Morro Rock.

The Nine Sisters are a cool chain of nine hills and small mountains in San Luis Obispo County, California. They stretch between Morro Bay and San Luis Obispo. People also call them the Morros.

How the Nine Sisters Formed

These unique peaks were created over 20 million years ago! During a time called the Miocene Epoch, hot, melted rock (magma) pushed up from deep inside the Earth. This magma cooled and hardened underground, forming very tough rock. The softer rock around these hard plugs has slowly worn away over millions of years. This process left behind the tall, rocky peaks we see today.

Two of these amazing rock formations are found inside Morro Bay State Park. The tallest of all the Nine Sisters is Bishop Peak. It stands at about 1,559 feet (475 meters) tall.

The Nine Peaks and Their Heights

Here are the Nine Sisters, listed from Morro Bay all the way to San Luis Obispo, along with their heights:

• Morro Rock 576 feet (176 m)
• Black Hill 665 feet (203 m)
• Cerro Cabrillo 911 feet (278 m)
• Hollister Peak 1,404 feet (428 m)
• Cerro Romauldo 1,306 feet (398 m)
• Chumash Peak 1,257 feet (383 m)
• Bishop Peak 1,559 feet (475 m)
• Cerro San Luis 1,292 feet (394 m)
• Islay Hill 775 feet (236 m)

What Makes the Nine Sisters Special?

Because these peaks are not always easy for people to reach, they are home to many different kinds of plants and animals. You can find Coastal sage scrub and California oak woodlands here. These areas are important for birds and other wildlife.

Their volcanic beginnings make them very interesting to geologists. Geologists are scientists who study the Earth's rocks and how they formed. The Nine Sisters are also a favorite spot for photographers. Many people also enjoy rock climbing on their slopes.

A Wide View of the Peaks

Panorama taken from Montaña de Oro State Park. Eight of the Nine Sisters are visible.