A petition has been launched to reopen the gates of the Phoenix Park to traffic.
Concern has been raised about congestion in the surrounding areas and campaigners say this will only increase with access routes cut off.
Only the Castleknock and Parkgate Street entrances are currently open to traffic as part of efforts to improve cycling and pedestrian facilities as more people use the green space during the lockdown.
The petition says it's now taking up to an hour to get from one end of the park to the other;
"Engine emissions from cars sitting on Chesterfield Avenue must surely be offsetting any potential environmental gain."
While it warns parts of the Park will become no go areas due to their isolation.
"This decision seems to have been rushed through with little forward thinking and engagement with local communities. Give the park back to the people and then work on alternatives to reduce car traffic" the petition says.