It lies near Lochwinnoch in Clyde Muirshiel Regional Park so it's not that far from Glasgow by car. Well, it would have been if the main route into Lochwinnoch wasn't being dug up and blocked off. We had to divert back through Howwood and then cross the A737 and work our way round the back route to Lochwinnoch.
Anyway, the trials of travelling on Scottish roads on a Sunday over, we parked in the Castle Semple car park and then strolled West along the banks of the loch towards the end of the path at Black Ditch Bay. From there we turned up towards the old railway, now a cycle path, and across into Parkhill Wood. The wood is a mazy place of paths and trails and there an old 18th century grotto beside a pond in the centre. We followed the path up to the top of Park Hill for some good views out over Castle Semple Loch and Barr Loch with the sun shining very brightly on the water.
Following the paths in the wood took us out towards the West end of the loch and the gothic Castle Semple Collegiate Church, built in 1504 to house the Castle's clergy. The castle itself, or the ruins of it, are nearby but all we could see looked to have built around by farm buildings. Wandering back up through the wood, there's a very muddy Rhododendron maze to navigate through to a viewpoint over the loch, where we could see some boats sailing on the sunlit water and managed to spot the old octagonal folly on top of Kenmuir Hill. From there it was back down to the wood and down to the loch shore path again and back to the park centre. We could have wandered back along the cycle path but it's fairly featureless and, being a high sided railway cutting, the views are non-existent.
The park centre has a tearoom and gift shop so we bought a couple of cups of tea and buns and, since it wasn't raining for a change, went out and sat down by the loch side to watch the windsurfers and wildlife. There were a large number of ducks and swans at the water's edge looking for some food off the tourists and they seemed to do pretty well at it. Then there were the Terns, a whole flock of them, squawking and buzzing around and trying to grab a snack any way they could. The ducks were mostly mallards but we spotted a lone Shelduck and a wee Goldeneye in the mix as well. We spent the rest of the afternoon just sitting by the water and enjoying the to-ing and fro-ing of the birds before heading back home.