Big deck chair.

If possible I always visit Kent Life Museum just outside Maidstone.  A place where my grandson loves.  You certainly get your steps in walking around the fields of different animals, play park, in and out of the various historical buildings types that you would find in Kent.  There were two unavailable to us as there was a wedding in the church and the village hall held the reception.  Unfortunately sandpits  were covered as it was wet in places and muddy.  My grandson loves puddles and mud.  He was suitably clothed but did get his wellies stuck.  His uncle got him out, but not before he had a muddy bottom!  He wasn't worried.  A great day for us all.