Boston Duck Tours, one of the city's most iconic tourist attractions, was expected to give a ride to its 12 millionth customer, Thursday.
"We want to thank our loyal patrons, and also invite those who have not yet taken our award winning tour," the company said in a release.
The milestone comes as Boston Duck Tours celebrates its 25th year in business. The company has been offering a 25% discount to New Englanders to celebrate the anniversary.
The company began giving tours of the city in 1994 and started with four duck boats. It now has a fleet of 28 amphibious vehicles and gives rides to an estimated 600,000 guests each season.
Boston Duck Tours changed its policy so that tours include both a driver and announcer following the 2016 death of a motorized scooter driver.