It celebrated its sesquicentennial year in 1988 with a number of special matches.
From the en.wikipedia.org
For the next four years, Gettysburg will host special sesquicentennial events.
From the latimes.com
The sesquicentennial celebration of Franklin College was held in mid-October 1937.
From the en.wikipedia.org
Oregon hails the sesquicentennial of its joining the Union as the 38th state.
From the buffalonews.com
When it came time to celebrate the signing's sesquicentennial, about 300 people came.
From the washingtonpost.com
The sesquicentennial is drawing new attention to the long-neglected event.
From the latimes.com
Try the sesquicentennial Poetry in the Park event on June 12 at Adams Park.
From the dailyherald.com
The Missouri Botanical Garden has constructed a floral clock for its sesquicentennial.
From the stltoday.com
For Big Sutling, the sesquicentennial couldn't have come at a better time.
From the businessweek.com
More examples
The 150th anniversary (or the celebration of it)
An anniversary (from the Latin anniversarius, from the words for year and to turn, meaning (re)turning yearly; known in English since c. 1230) is a day that commemorates and/or celebrates a past event that occurred on the same day of the year as the initial event. ...
A 150th anniversary; Occurring every 150 years; Of, or relating to a sesquicentenary
The prefix sesqui is from the Latin and means one and one-half of whatever follows. Sesquicentennial refers to a period of one and one-half centuries, 150 years. The prefix is actually a contraction of two parts, semi, which means one-half, and the enclitic que which means "and". ...