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Castlereagh, County Down


Ir. An Caisleán Riabhach ‘the grey castle’ 


District forms a suburb, 4km SE of Belfast city centre

The castle (no trace of which remains) was probably called riabhach ‘grey’ because it was made of stone. It was sometimes known as Castle Clannaboy because it was the stronghold of the O’Neills of Clannaboy (alias Clandeboye) in the second half of the sixteenth century.  It was sold by Sir Conn O’Neill (who gave name to Conn’s Water) to Sir Moses Hill in 1616.  The site is marked by the Orange Hall close to Castlereagh Presbyterian church on Church Road. The name Castlereagh is applied more widely to an area north of the townland (in neighbouring Lisnasharragh) and closer to the city of Belfast, as shown on the OSNI Belfast street map.  This area is adjacent to Castlereagh Road and Castlereagh College is located here. Castlereagh has also given name to two baronies (Castlereagh Upper and Lower) and to the local government district of Castlereagh Borough.


McKay, P. (2007): A Dictionary of Ulster Place-Names, p. 38; PMcK, 2009; with additions PT, 2012.

Additional Information

See also the baronies of Castlereagh Upper and Castlereagh Lower

Historical name form

Old FormRef. DateReference

(?) Grayy Cambe

1591Hondius Map

Caislen Riabhach ""grey castle""

1834cJ O'D (OSNB) E 124

An Caisleán Riabhach "" the speckled castle""

1999Cel. Ulst. Tds 11

An Caisleán Riabhach ""the grey castle""

1999Dict. Ulst. PN 38

stye brae "" steep hill""

1999Cel. Ulst. Tds 11

An Caisleán Riabhach ""the grey castle""

2001NIPNP replies PMcK/KH

An Caisleán Riabhach ""the grey (grizzled) castle""

2003HMC replies HMCjun03
Castell Rewe1574Sav. Ulst. 367
Castell Reage1580cSE Ulster Map
Ca[s?] Raiogh1590Dartmouth Map 5
C[as] Reagh1590cJobson's Ulster (TCD)
C. Reache1595Mercator's Ulst.
C.Reache1595Mercator's Ulst.
Ca: Reaugh1599Boazio's Map (BM)
Ca Regh1603Bartlett Maps (Esch. Co. Maps) 1
Ballicastle-reogh1605Inq. Ult. (Down) $2 Jac. I
Ballinecarrowreogh1605CPR Jas I 73a
Ca: Reaugh1609cBoazio's Map (NG)
Reagh1610Speed's Ulster
Reagh1610Speed's Antrim & Down
Reagh1610Speed's Ireland
C, Reagh1610cNorden's Map
Balle-Castlereogh1623Ham. Copy Inq. [1623] xl
Castle-Reogh1623Ham. Copy Inq. [1623] lvi
Castlereagh1623Ham. Copy Inq. [1623] lv
Castlereagh1623Ham. Copy Inq. [1623] lvi
Castlereagh1627CPR Chas I 233
Castlereagh1632Inq. Ult. (Down) $29 Car. I
Bally-castlereagh1640Inq. Ult. (Down) $86 Car. I
Castellreagh1659cCensus 1659 88
Castlereagh1661BSD 123
Castlereagh1745Map of Down (OSNB) E 124
Castlereagh1810Wm. Map (OSNB) E 124
Castlereagh Upper
Parish in 1851
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