The rest of the story.
I mentioned the money-in-the-mattress solution for keeping money safe. A crackpot lead in like that deserves to have the whole story told.
I used to have a large safe in my basement. It was a thing of beauty, made in 1800's with ornate pre-Victorian bas reliefs and bands of steel that would thwart any attempts to open it. When my home was flooded, the safe mechanisms seized, making it a square steel 'boulder' in the basement.
I called for estimates. It was cheaper to buy another safe than to open this one, and had estimates to haul it away that were several grand, assuming that I first moved it out of the basement to a place that a crane could lift it to a truck. $$$$$!!!
I spent a few hours with a drill and cutting wheel to open a small hole through the first steel layer to the fireproof powder/cement layer, and a few hours trying to move it a few feet. Clearly, none of these would work.
I did, however, learn how Stonehenge boulders were moved by a DIYer in England using a rock to balance the boulder and it being swiveled (walked) inch by inch, and that fire resistant ratings come from the number of inches of drywall and concrete that is in the walls.
What eventually happened was the basement floor was jack hammered out, I poured new footings to support my house, a big hole was dug in the floor, the safe was pushed in, then refilled the hole and the floor was re-poured. Except for the hole, this was work that I had to do anyway.
I still had that small child inside that liked cubbyholes to hide my treasures, and not wanting to spend another few grand to have a new safe moved in, incorporated my hidden cache under my new floor. I guess that after I lost three banks and credit unions, I became that depression-era crank that doesn't trust banks.
Mutual funds ARE safe tho