WATCH: Lincoln Memorial undercroft receives $69 million renovation

For 100 years, the Lincoln Memorial has been a Washington, D.C., staple — it’s seen by millions of visitors each year.

But what’s been hidden from the public all this time is the undercroft beneath the memorial.

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Now, thanks to a big donation and a huge renovation, the undercroft will be open to the public in 2026.

“There are 122 concrete pilings, 40 to 50 feet tall, that the memorial was built on. This project is going to let visitors get a view of the area,” said Mike Litterst, a National Park Service spokesman.

The cavernous area beneath the monument is being turned into a museum.

“We will talk about the construction of the Lincoln Memorial and how its meaning has changed over time,” Litterst said.

The undercroft will be transformed into a 15,000-foot exhibit space — featuring floor-to-ceiling glass walls and a theater where visitors can learn about prominent figures