The hustle and bustle that were features of Donaghadee during the Packet Ship days declined but the town was left with a magnificent harbour, hotels and boarding houses and these were turned into an advantage. As Belfast grew, the increasingly prosperous merchants of the city were attracted to the idea of holidays by the sea, and where better than Donaghadee with its dry climate and invigorating atmosphere? So as the 19th century progressed into the 20th, Donaghadee became established as a major holiday resort.
The Norman family most closely associated with the Motte was de Coupland, who also gave their name to the Copeland Islands, about a mile offshore. The main island is a popular destination for summer visitors. Lighthouse Island, the second largest, has the remains of an old lighthouse and is an important bird sanctuary, whilst to the east lies Mew Island.