Blackrock Park is a pleasant green area overlooking Dublin Bay, in Blackrock County Dublin, and boasts a well equipped children's playground, cycle path and trees.
There is also a picturesque pond containing a small island, and swans can regularly been seen there. The Peace Fountain in the pond was constructed in 1986 to mark International Year for Peace.
Blackrock had a beach that was a popular bathing place until the construction of the railway close to the shoreline. The space between the shore and the railway created an area that flooded with sea water at high tide. This created a malodorous salty marsh similar to that at Booterstown marsh. This marsh was a cause of local discomfort for years until it was decided by the Blackrock Town Commissioners (established in 1860) to fill the area in and create a park. The park, which stretches from Blackrock to Booterstown (encompassing Williamstown), was created in the early 1870s. The granite gates at the main entrance once belonged to a house called Vauxhall. The gardens at the entrance were part of the gardens of the old house.
The Williamstown Martello Tower in Blackrock Park was built between 1804–1806. When the tower was built, it would have been surrounded by sea water at high tide as it was built in the inter-tidal beach area. The tower became isolated from the sea when the construction of the railway took place, but sea water still flowed into the area at high tide. It wasn't until the filling in of the area to form the Blackrock Park that the tower was to be on dry land. That part of the tower which is visible today is actually the first floor as the ground floor is buried underground.