Imagine a family holiday in a submarine. Not one of those Russian nuclear behemoths slinking hundreds of metres beneath the waves, but a tiny capsule with scant room to swing a fish in. That's how I envisaged our first trip around Britain in our new camper van.
Less than five metres long and just over two metres wide, the converted Toyota van is scarcely bigger than a family saloon. It's a squeeze for three people. Add a gaggle of dolls and stuffed toys - the inseparable travel companions of Astrid, my two-year old daughter - and the feeling of claustrophobia becomes difficult to suppress.
Yet driving along the motorway towards Devon, I remembered why we bought this vehicle in the first place.
It went beyond the lure of the road. It offered the promise of a freedom rarely glimpsed by parents. It provided the liberty of a snail or a tortoise, the independence of some creature which carries their dwelling with them.
By 4pm, with the watery sun already heading for the horizon, we had nearly reached Bristol and still had no inkling where we would stay. This spontaneous approach to travel, with even a hint of improvisation, is difficult to achieve as parents of young children. Planning, preparation, forethought: these tend to be the dominant modes when travelling with kids.
We pulled off the motorway and headed on a small road through Gloucestershire's undulating hills. Flicking through the pages of The Caravan Club book (www.caravanclub.co.uk) we found a campsite near a village called Stonehouse.
Many of the sites in this book are little more than farmers' fields with water and a waste disposal. More opulent ones have electricity. This one was a small, tree-lined field with two caravans already settled in. The grey-haired occupants eyed us suspiciously as we pulled up and Astrid sprung out.
As we settled down, the fears about meagre space began to seem well founded. Astrid ran in and out of the camper van trailing mud around. She turned on the tap and nearly flooded the kitchen. She pressed lots of buttons on the dashboard and tried to climb into the roof bed. She was, in short, becoming frantic.
Then a chicken came into the camper van. Confronted by this clucking beast, Astrid stopped stock-still. Then she chased it outside. From then on, for some reason, everything became calmer. Astrid seemed to grow accustomed to the rules and requirements of limited space.
As darkness fell and we prepared to sleep, the tiny space become a boon. With the blinds down and the beds made, the camper van was like a cocoon. Astrid slept in this womblike space for nearly 12 hours when she usually sleeps for seven.
The fresh air, the peripatetic lifestyle, even the cramped quarters: they all seemed to suit her. Camper van, we salute you.
