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How much public land is there in Blanchardstown, Castleknock and Ongar?

937 ha in Blanchardstown, Castleknock and Ongar is on the Land Development Agency's register of relevant public land, across 486 sites, as of 25 Sep 2026. The largest holder is Fingal County Council, with 353 ha.

From public registers, checked 25 Sep 2026. Updated nightly.

  • 353 haFingal County Council
  • 212 haDublin City Council
  • 140 haThe Industrial Development Authority
  • 46.5 haMinister for Agriculture, Food and the Marine
  • 45.4 haThe Minister for Education and Skills

The largest public sites in Blanchardstown, Castleknock and Ongar

  1. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 38.9 ha · source

    Publicly owned land

    38.9 ha, Held by The Industrial Development Authority

  2. Public land in Castleknock

    Castleknock · Fingal · 32.41 ha · source

    Publicly owned land

    32.4 ha, Held by The Office of Public Works

  3. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 31.27 ha · source

    Publicly owned land

    31.3 ha, Held by Fingal County Council

  4. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 27.33 ha · source

    Publicly owned land

    27.3 ha, Held by Dublin City Council

  5. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 26.9 ha · source

    Publicly owned land

    26.9 ha, Held by Dublin City Council

  6. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 25.15 ha · source

    Publicly owned land

    25.2 ha, Held by Electricity Supply Board

  7. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 24.33 ha · source

    Publicly owned land

    24.3 ha, Held by Fingal County Council

  8. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 20.43 ha · source

    Publicly owned land

    20.4 ha, Held by Institute of Technology Blanchardstown

  9. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 19.47 ha · source

    Publicly owned land

    19.5 ha, Held by Health Service Executive

  10. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 19.07 ha · source

    Publicly owned land

    19.1 ha, Held by Dublin City Council

  11. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 14.96 ha · source

    Publicly owned land

    15.0 ha, Held by Minister for Agriculture, Food and the Marine

  12. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 14.33 ha · source

    Publicly owned land

    14.3 ha, Held by Fingal County Council

  13. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 13.77 ha · source

    Publicly owned land

    13.8 ha, Held by The Industrial Development Authority

  14. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 13.25 ha · source

    Publicly owned land

    13.2 ha, Held by The Industrial Development Authority

  15. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 13.12 ha · source

    Publicly owned land

    13.1 ha, Held by The Industrial Development Authority

  16. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 12.2 ha · source

    Publicly owned land

    12.2 ha, Held by Dublin City Council

  17. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 11.87 ha · source

    Publicly owned land

    11.9 ha, Held by The Industrial Development Authority

  18. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 11.2 ha · source

    Publicly owned land

    11.2 ha, Held by The Industrial Development Authority

  19. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 11.18 ha · source

    Publicly owned land

    11.2 ha, Held by Dublin City Council

  20. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 10.99 ha · source

    Publicly owned land

    11.0 ha, Held by Minister for Agriculture, Food and the Marine

  21. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 10.96 ha · source

    Publicly owned land

    11.0 ha, Held by Fingal County Council

  22. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 9.76 ha · source

    Publicly owned land

    9.8 ha, Held by Minister for Agriculture, Food and the Marine

  23. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 9.21 ha · source

    Publicly owned land

    9.2 ha, Held by Dublin City Council

  24. Public land in Blanchardstown-Mulhuddart

    Blanchardstown-Mulhuddart · Fingal · 9.2 ha · source

    Publicly owned land

    9.2 ha, Held by Dublin City Council

  25. Public land in Castleknock

    Castleknock · Fingal · 9.15 ha · source

    Publicly owned land

    9.2 ha, Held by Fingal County Council

Showing 25 of 486. See them all →

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More about Blanchardstown, Castleknock and Ongar

Is there development land for sale in Blanchardstown, Castleknock and Ongar?
Buildable found 62 sites in Blanchardstown, Castleknock and Ongar with a public sign they could come to market, as of 25 Sep 2026: 26 council sites proposed for sale, 2 sites with planning permission running out or recently expired, 2 derelict sites on the register and 41 stalled builds. These come from public registers, not agents' listings, so many are not advertised yet.
How many development sites are there in Blanchardstown, Castleknock and Ongar?
Buildable tracks 1,665 development sites in Blanchardstown, Castleknock and Ongar, as of 25 Sep 2026: every site with a public reason it could be built on or sold, from the councils' and national registers. They include 9 permitted schemes not started, 13 derelict sites, 32 council land sales and 41 stalled builds.
What are the largest development sites in Blanchardstown, Castleknock and Ongar?
485 development sites in Blanchardstown, Castleknock and Ongar are a hectare or larger, as of 25 Sep 2026. The largest is public land in Blanchardstown-Mulhuddart, at 38.9 ha (publicly owned land).
How much land in Blanchardstown, Castleknock and Ongar is on the RZLT map?
1,104 ha of land in Blanchardstown, Castleknock and Ongar is on the Residential Zoned Land Tax map, across 1,093 parcels (2027 draft RZLT map), as of 25 Sep 2026. 991 ha of it has no live permission for 10 or more homes. The tax is 3% of market value a year, collected by Revenue on maps the councils make.

Data as of 25 Sep 2026. Sources: Land Development Agency, Register of Relevant Lands.

Cite this: How much public land is there in Blanchardstown, Castleknock and Ongar? Buildable, data as of 25 Sep 2026. https://buildable.ie/q/public-land-dublin-15

Facts from public registers, not advice. Every question · How it works