Families had a tea party with a pair of sheep to celebrate the reinstatement of the ha-ha at Hillworth Park in Devizes.
The walled trench was designed to separate grazing animals from gardens without spoiling the view and dates from the 18th century.
Devizes Town Council bought Hillworth Park after the Second World War but by then the ha-ha had been lost and only the top stones of the wall were visible.
After the refurbishment of Hillworth Park two years ago, the Heritage Lottery Fund awarded £50,000 for the restoration of the ha-ha.
To celebrate the town council held a tea party while two sheep from Rowdefield Farm were contained on one side of the ha-ha, to show how it was used.
Four members of the orchestra Southern Sinfonia played music and about 150 people attended.
Carole Berry, direct services manager at the town council, said: “A lot of people said how lovely the ha-ha was. A lot of people didn’t know what a ha-ha was so we explained its purpose.”