The reference to leeks should tell you which country you're in. Google that, together with 'wildlife centre' and I think that everything will fall into place for you. (I've only had a very quick look but everything seemed to be fitting together well for me when I used that as my starting point).
The river is the Afon Teifi on which stand Newcastle Emlyn, the "first-mentioned town" and home to Dairy Partners' mozzarella plant (hence the Italian references), Cilgerran Castle, the "second fortress" perched on a cliff and having two towers, and Cardigan, the "second town" with its southern entrance guarded by a castle.