Don,
I work in Rotterdam and a number of my friends take their caravans to winter camp-sites - for skiing trips.
So they invested in snow tyres - which need to be stored properly for 9 months of the year, and the right way to store tyres is:
1. In the dark or subdued light
2. Inflated at normal pressures
3. Vertically off the ground, on a wall mounted wheel hub or mounting bracket
They store their tyres (and the steel wheels they bought for winter use) with a specialist storage centre in Rotterdam who do all this for them.
Robert
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