The river Conwy is the third largest river discharging into the Irish Sea along the North Wales coast. It drains a catchment of 678 km2, the main drainage channel covering a distance of 55 km. The Upper Conwy drains the Migneint (one of the largest blanket bogs in Wales and a major carbon store) and passes through improved grazing land and conifer plantations. The lower Conwy flows through extensive flood plains and meets the tidal limit around 20 km inland from the estuary mouth. Three major tributaries (the Machno, Lledr and Llugwy) join the upper Conwy from the west, and drain many of the high mountains of Snowdonia. The tidal Conwy receives further inflows from a number of smaller tributaries. The catchment is predominantly rural, with sheep farming as the main land-use to the west and mixed dairy, beef and sheep farming to the east. The lowland flood plain area has some arable farming and a large afforested area to the west. The upper catchment is given over mainly to sheep farming. There is extensive semi-natural woodland cover in most sub-catchments including important areas of wet woodland. There are a number of initiatives currently underway in the catchment, including: quantifying surface water quality from a suite of locations on the Conwy, its tributaries and in the estuary; fluvial monitoring characterising the physical behaviour of a peatland headwater stream; characterisation of the physical behaviour of a peatland headwater lake. Carbon flux measurements are ongoing within the Migneint area, supported by continuous weather station and water table measurements and activities to investigate carbon fluxes. The Snowdon/Yr Wyddfa terrestrial and freshwater ECN site is located adjacent to the Conwy catchment.