Castlereagh River
The Castlereagh rises 20 km west of Coonabarabran in the heart of the Warrumbungle mountains at an elevation of about 850 metres. From its commencement upstream in the mountains the river initially flows east through the town of Coonabarabran. It then arcs round south and southwesterly to the village of Ulamambri, then south to Binnaway, and SSW to the small town of Mendooran which lies at the eastern side of the river's hook-shape. From here the Castlereagh flows in a westerly direction at the flattened bottom of the hook and then turns north-westerly towards the town of Gilgandra. From Gilgandra it continues to run northwesterly across the plains through Gulargambone and Coonamble, then continuing across expansive plains, with no urban centres, where elevations are less than 200m, until it joins the Macquarie River at its uppermost reaches beyond the Macquarie Marshes. Its confluence with the Macquarie is about 65 km SW of Walgett. Not far from the Castlereagh/Macquarie confluence the Macquarie itself joins the Barwon River at a place about halfway between Walgett and Brewarrina.
Killorglin
The River Laune, ("An Leimhain") in Irish, flows approximately 20 km to drain Killarney’s Lough Leane into the sea at Castlemaine Harbour. The Laune carries most of the rainfall from the MacGillycuddy Reeks, Ireland’s highest mountain range. Many streams on the south side of the Reeks drain into Killarney’s Upper Lake before filtering down to Lough Leane. As the River Laune drains Lough Leane to the sea, it is fed by two rivers running north from the Reeks, the River Loe from the Gap of Dunloe and the Gaddagh River from the heart of the Reeks. Another tributary, the Cottoners River, carries rainwater from the west of the Reeks. On the southern side of the bridge, a low embankment runs upstream for about 1 km towards Killarney. This is part of over 40 km of embankments that prevent the sea from flooding low-lying land around Castlemaine Harbour. These embankments exist due to Napoleon’s dominance in Europe around the year 1808. The British government were looking for alternative sources of hemp to make sailcloth for their navy to defend against a possible invasion. If the bogs of Ireland could be drained then they could be used to grow this raw material without impacting on the existing agricultural output of the country. In 1811-1812 Alexander Nimmo surveyed and mapped over 76,000 acres (30,700 ha) of land on the Iveragh Peninsula for the Bogs Commission. Over 17,000 acres (7,000 ha) of this were on the sea shore area of the Laune River, Lower River Maine and Castlemaine Harbour. Now over 200 years later, these stone and earthen banks still prevent high tides flooding much of this land. The banks vary from 1m to over 5m in height. Sluice gates allow water drain out at low tide and prevent rising tides from flooding the land. The banks run from the townland of Tullig near Cromane, to Killorglin, part way up the Laune, around the area of Callinafercy, up both sides of the River Maine and along the north side of Castlemaine Harbour, part way to Inch. Various major repairs are evident where large rocks and concrete have replaced the stone and earth, however much of the original banks are still intact, a testimony to the skilled workers who built them.
The Killorglin river bank walk and the Astellas river bank walk downstream of the Iron Bridge are both part of these 200-year-old embankment.