Place in a fire/water resistant bag 90% cash, 10% Bitcoin. In the event of hyperinflation the Bitcoin will hopefully gain (or at least preserve value)-- and it

Place in a fire/water resistant bag 90% cash, 10% Bitcoin. In the event of hyperinflation the Bitcoin will hopefully gain (or at least preserve value)-- and it can be transferred online, which the cash cannot. (And in the event of a total bitcoin collapse you still have 90%). Re-balance it once a year or so. It doesn't take much to make missing out on the 0.5% interest rate of a high rate savings account into not much of a problem.