Further restrictions on cars travelling through the Phoenix Park are being planned by the Office of Public Works.
Six "peripheral gates" closed during the Covid-19 lockdown will now remain shut although the main entrances at Castleknock and Parkgate Street will remain open.
In a statement, the OPW said in recent weeks there has been a "sea change" in how visitors enjoy the biodiversity and landscape of the park.
It has increased space for pedestrians and cyclists by 33%, introducing 7km of cycle lanes along the main thoroughfare of Chesterfield Avenue.
OPW Commissioner John McMahon said further measures to reduce car traffic are likely, and reducing the amount of 'through traffic' was a priority so as to improve the environment for cyclists and pedestrians.
He said the park is Dublin's "green lung" adding that the "OPW is determined to ensure that the park is a safe, quiet, green space for our visitors, where flora and fauna thrives and where visitors' health and wellbeing can be enhanced through experiencing the natural environment in the park".
The car restrictions follow calls by An Taisce and the Green Party for a ban on through traffic in the park.