The White Tower of London
Similar great keeps to the White Tower with an apsidal chapel only exist at Colchester in the British Isles and Ivry le Bataille in France.
Various English examples of twin towered gatehouses like the one at the Tower survive at Beeston, Bungay, Clifford, Dover, Longtown, Pembridge, St Briavels and Whittington. In Wales they exist at Caerphilly, Carmarthen, Chepstow, Criccieth, Degannwy, Dinas Bran, Llawhaden, Neath, Oystermouth, Powis, Rhuddlan, Tinboeth and White Castle. In Scotland they can be found at Kildrummy and Urquhart and finally elsewhere in Ireland at Carrickfergus, Castle Roche, Dungarvan, Limerick and Roscommon.
Paul Martin Remfry