REFERENCE	DESCRIPTION	PFX	DXCC	EURA CODE
EUCC-GB-BGW	Principal area of Blaenau Gwent	GW	294	EURA-142
EUCC-GB-BGE	Principal area of Bridgend / Pen-y-bont ar Ogwr	GW	294	EURA-142
EUCC-GB-CAY	Principal area of Caerphilly / Caerffili	GW	294	EURA-142
EUCC-GB-CRF	Principal area of Cardiff / Caerdydd	GW	294	EURA-142
EUCC-GB-CMN	Principal area of Carmarthenshire / Sir Gaerfyrddin	GW	294	EURA-141
EUCC-GB-CGN	Principal area of Ceredigion	GW	294	EURA-141
EUCC-GB-CWY	Principal area of Conwy	GW	294	EURA-140
EUCC-GB-DEN	Principal area of Denbighshire / Sir Ddinbych	GW	294	EURA-140
EUCC-GB-FLN	Principal area of Flintshire / Sir y Fflint	GW	294	EURA-140
EUCC-GB-GWN	Principal area of Gwynedd	GW	294	EURA-140
EUCC-GB-AGY	Principal area of Isle of Anglesey / Ynys Mon	GW	294	EURA-140
EUCC-GB-MTY	Principal area of Merthyr Tydfil / Merthyr Tudful	GW	294	EURA-142
EUCC-GB-MON	Principal area of Monmouthshire / Sir Fynwy	GW	294	EURA-142
EUCC-GB-NTL	Principal area of Neath Port Talbot / Castell-nedd Port Talbot	GW	294	EURA-142
EUCC-GB-NWP	Principal area of Newport / Casnewydd	GW	294	EURA-142
EUCC-GB-PEM	Principal area of Pembrokeshire / Sir Benfro	GW	294	EURA-141
EUCC-GB-POW	Principal area of Powys	GW	294	EURA-141
EUCC-GB-RCT	Principal area of Rhondda Cynon Taf	GW	294	EURA-142
EUCC-GB-SWA	Principal area of Swansea / Abertawe	GW	294	EURA-142
EUCC-GB-TOF	Principal area of Torfaen / Tor-faen	GW	294	EURA-142
EUCC-GB-VGL	Principal area of Vale of Glamorgan / Bro Morgannwg	GW	294	EURA-142
EUCC-GB-WRX	Principal area of Wrexham / Wrecsam	GW	294	EURA-140

To detect the Area look at QSL or eQSL card:

This eQSL show the QTH: Amlwch. Put this info into Wikipedia and you will find this:

The Area is the Isle of Anglesey, and the code is EUCC-GB-AGY