14,000 people have objected to plans to redevelop the Hellfire Club in the Dublin mountains.
South Dublin County Council wants to turn the area into a major tourist attraction with a €15m investment.
The planning proposal includes a visitor centre with a viewing platform.
But Fine Gael TD Colm Brophy is worried about the extra traffic it will bring to the area.
He said: "I think Dublin have put forward a scheme which could lead to a permanent gridlock situation on weekends and busy summer days."
- Digital Desk