Hearst Castle has been missing one of its main attractions since 2014, when the California Department of Parks and Recreation discovered a series of problematic cracks in the foundation of the 345,000-gallon Neptune Pool. The discovery led to a four-year, $10 million restoration project that involved replacing more than 9,000 square feet of marble tile and installing a new waterproofing system in the nearly 90-year-old pool.

This week, crews added the final touch: the famously crystal clear water.

Built between 1919 and 1947 by billionaire William Randolph Hearst and architect Julia Morgan, the 115-room historic castle sits atop La Cuesta Encantada (“The Enchanted Hill”), and became a state historic landmark in 1958. Neptune Pool is one of the most recognizable features of the estate, which draws 750,000 visitors to San Simeon in San Luis Obispo County annually. Its Roman- and Greek-style architecture and art deco statues have appeared in countless photographs since the castle opened.

“We are pleased that visitors can again enjoy the artistry of Neptune Pool,” said Dan Falat, California State Parks District Superintendent, in a release. He reassures visitors that “this fully restored structure and other improvements ensure that water is being used efficiently and wisely for the long term.”

You can see pictures and video of the refilling process on the Hearst Castle website—but the striking pool is best seen in person. Although regular tour access to the pool is still a couple weeks away, you can see it from several vantage points on the grounds. Book a tour here; tickets start at $25 for adults and $12 for kids.

Make a road trip out of your visit by driving north from San Luis Obispo County on Highway 1. Pull over along the way to see these 10 Most Instagrammable Stops, or opt for one of these 5 ways to do the drive. While you're there, check out some more fun things to do in San Luis Obispo County.