These postcode districts cover much of south Powys, including Llandrindod Wells, Brecon, Builth Wells, Presteigne, Knighton, Rhayader, Llanwrtyd Wells and Llangammarch Wells.
The LD6 district also covers one isolated farmhouse in Ceredigion.
The LD7 and LD8 districts extend across the border into England, covering very small parts of Shropshire and Herefordshire.
The LD area is sparsely populated and contains fewer postcodes than any other area on the British mainland, except for the KW area in the north-east of Scotland.
[3] The approximate coverage of the postcode districts: