This is a 3 litre box, so it has plenty of room for large swaps and trackables.
There are several ways you could reach this cache, but I recommend the peaceful walk along the Cam from Waterbeach (1½ miles from Bottisham Lock at the north-east corner of Waterbeach; 2½ miles from Waterbeach station) or even Cambridge.
The cache is hidden near the lock. It is not really suitable for smaller children owing to the close proximity of water but larger children (say, KS2+) may enjoy it.