Main gate of the of the complex which houses the Office of the Taoiseach or Irish prime minister. The buildings were constructed between 1904 and 1922. Around 1990 they were extensively cleaned and restored.
More info on the Department of the Taoiseach website.
The gate was just closing after allowing a car to exit.
Dublin Government Buildings / Department of the Taoiseach
Dublin, Republic of Ireland, Irish government, photos of Dublin government buildings