For many visitors, the town of Lahaina is a place to go for tropical beaches. But for residents of Hawaii, it is a trove of history.

Its heritage museum, in a landmark courthouse, houses artifacts from before the rest of the world knew Hawaii existed. Its oldest building, the Baldwin Home, was occupied by the 19th-century physician who saved Maui from an epidemic of smallpox. Its central feature, a sprawling 150-year-old banyan tree, was planted to commemorate the arrival of Christian missionaries in 1873.

On Wednesday, that legacy and more appeared to be in ashes, consumed by the hurricane-driven wildfires that have devastated the island of Maui, razing much of the historic district of Lahaina, once Hawaii’s royal capital, in a matter of hours.

“We had no preparation, no warning, nothing,” said Theo Morrison, the executive director of the Lahaina Restoration Foundation, which manages more than a dozen historic sites in the town. Ms. Morrison, a longtime resident and the mother of a firefighter who has kept her apprised of the damage, spoke from an East Coast airport on Wednesday. She left Maui a day before the fires had broken out on Tuesday night, bound for Europe on family business, she said.

“I never would have left if I’d known what was coming,” she said. Whipped by wind, the fires blew through nearby grasslands and roared through the historic tourist town.

The Baldwin Home, which houses the foundation’s main office, appears from news photos to have burned to the ground after its roof caught fire, she said.

The home contained the wooden rocking chairs that the family of the Rev. Dwight Baldwin had shipped all the way from their East Coast home in the 1830s, their son’s antique shell collection and the medical instruments that Dr. Baldwin, a missionary and physician, had used to vaccinate much of Maui against smallpox.

“The Old Lahaina Courthouse roof is entirely gone,” Ms. Morrison said. “And so is the beautiful heritage museum we had there. The top floor had ancient Hawaiian things, things from the monarchy and plantation and whaling periods, objects from all of Lahaina’s eras.”

Most of the museum’s important documents have been preserved online, she said, and she is hoping that the island will restore at least some of the buildings when the fire abates.

But she is preparing herself for some major losses. “This is the worst destructive thing that has happened in this town’s entire history,” she said.