I was at GRONI this morning and they have a sheet on the wall giving rough indications of the area covered by each sub district within Belfast. I jotted it down for the benefit of all those Rootschatters who have been scratching their heads over when these places are on the map. Hope this helps

Belfast Registration Districts
Urban
1 Fleet St, York Dock, Jennymount St
2 Limestone Rd, New Lodge
3 Shankill, Clifton Park Ave, Old Lodge Rd
4 Lisburn Rd, Botanic, Ulsterville
5 Divis St, Millfield, Norfolk St, Argyle St
6 Eglantine Ave, Wellington Pk, University St, Rugby Rd
7 Greencastle, Whitehouse, Whitewell
8 Woodvale Ave, Ligoneil Rd, Alliance St, Ballygomartin Rd
9 Falls Rd, Broadway
10 Springfield Rd, Brookmount, Mayo St, Cambrai St
11 Ormeau Rd, Ravenhill Rd,Woodstock Rd, Castlereagh Rd
12 Beersbridge Rd, Connswater
13 Connsbrook, Belmont Church Rd, Bloomfield Ave, Knock
14 Belmont Rd, Ballyhackamore
15 May St, Joy St, Bosnia St
16 Albertbridge Rd, Mountpottinger Rd, Queens Island
Rural
1 Whiteabbey, Cloughfern, Jordanstown
2 Cavehill Rd, Ballysillan, Glencairn
3 Finaghy, Stockmans Lane
4 Glengormley, Carnmoney, Ballyhenry
Castlereagh
1 Dundonald, Gilnahirk
2 Holywood
3 Cregagh Rd, Ballygowan Rd, Ladas Drive