Hertfordshire postcode districts

AL1 AL10 AL2 AL3 AL4 AL5 AL6 AL7 AL8 AL9 CM19 CM20 CM21 CM22 CM23 EN10 EN11 EN2 EN4 EN5 EN6 EN7 EN8 EN9 HA5 HA6 HA7 HP1 HP2 HP23 HP3 HP4 HP5 HP8 LU1 LU2 LU6 SG1 SG10 SG11 SG12 SG13 SG14 SG15 SG2 SG3 SG4 SG5 SG6 SG7 SG8 SG9 SL9 UB9 WD17 WD18 WD19 WD23 WD24 WD25 WD3 WD4 WD5 WD6 WD7 WD99