Doom physical emergency fund?

Anyone hold physical dollars in large amounts in their house?

I already have a large emergency account. So in a case of a bad situation I can withdraw it fast.

But let's say in a doom situation where the banks collapse and you don't get to withdraw your cash... is it a good idea to have an emergency emergency fund?

I know it's probably a bad idea to store it unprotected in your house due to fire, theft, etc...

Do you guys have one of those?

Thanks