Demolition on the building began Thursday at the corner of Highway 146 and Nasa Parkway. By Saturday evening, the building was completely gone.
The improvement project includes widening the road from Red Bluff to south of the Galveston/Harris County line, according to TxDOT.
A number of Seabrook businesses had to be removed to make room for the work. While some are already gone, others are weeks away from the same fate as the "Triangle Building."
"It's an odd building. There's no other building like that in a lot of cities," said Kathi Bell, a Clear Lake resident. "It's a real landmark for us."
Over the past 80 years, the building served as a bait and tackle shop, a real estate agency, and an attorney's office.
The building's owner recently settled with the State of Texas over a purchase price.
"I understand. It's progress. It's still going to be very sad because it is a treasure," Bell said. "This is a historical landmark for Seabrook."
The demolition lasted a day, but TxDOT said it will take several days to remove the debris.
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