School trip to the Château at Nantes

We stayed at the excellent campsite at Le Petit Port, Nantes - we seem forever stopping off at Nantes when we travel through France! There is a convenient tram line from the gate of the campsite to the city centre. 
In our ramblings, we stopped outside the château, and saw several groups of schoolchildren in the area - here some are crossing the bridge into the château. 
The moat contains water but also grassy areas that are used by people to sit in the sunshine - some can be seen beyond the bridge.