Castlemaine is known for being the birthplace of the Wild Colonial Boy whose exploits in Australia were made famous in the well known ballad. There are many different versions of the Irish/Australian ballad 'The Wild Colonial Boy'. The song tells of a young Irish emigrant convicted of highway robbery and sentenced to death. After escape this Robin Hood type character robbed from the rich to feed the poor until he was captured and shot. The Irish version of the song is about ‘Jack Duggan’ who left Castlemaine in the early 1800s. A bar in the village is named after him.

“There was a wild colonial boy, Jack Duggan was his name, He was born and raised in Ireland in a place called Castlemaine."

The area around Castlemaine is of major ecological importance, with coastal habitats of excellent quality. Castlemaine Harbour is a very important site for wintering waterfowl providing good quality feeding and roosting habitats for an excellent diversity of waterbirds, including geese, waders, divers and seaduck. Species of birds found here include Brent geese, cormorants, shelduck, wigeon, dunlin, redshank, golden plover, oystercatcher. Part of this area is a Statutory Nature Reserve. it includes long stretches of river and stream which are excellent habitats for Salmon, Lamprey and Otter. 

The protected natterjack toad is one of the rare animals found in the area.

 Castlemaine takes its name from a defensive castle built on a bridge spanning the River Maine.The River Maine would have flooded in winter and was a strategic river crossing in Munster. A pen and ink map drawing depicting the Castle on the bridge at Castlemaine exists in the UK National Archives, Kew, England. The drawing is of the Siege of Castlemaine by Sir John Perot, Lord President of Munster, in 1572 and was probably drawn shortly after Sir John Perrot's victory in August 1572. The map shows the castle spanning the River Maine, Perot's camp, two Gallyglas camps, Macarte More's camp, two cannons firing at the castle, the first camp, the abbey, the ferry, wood and bog. The siege was part of a campaign by Perot against rebels.