If you put a lot of money in a bank then there is a counterparty risk the bank defaulting or you getting a haircut. Money in a bank is no longer "yours".
Some hardcore asset management schemes store physical US bills in a high security storage. You will pay % negative yield on yearly storage cost, but cash is truly yours and you can withdraw any day.
Also in the EU, with some fintech startups, you can now open a bank account which comes with a IBAN number from a central bank of Lithuania - essentially your money is stored within European Central Bank system. You will have negative ECB interest and pay some extra, but there is no counterparty risk unless the whole European banking system collapses.
It should be noted that "a lot of money" in this context means more than whatever limit your country has on deposit insurance. In the US, up to $250k is insured by the government against default, and it goes per account type and per bank, so you could easily store, say, $2M fully insured.
But of course, this does not insure you against systemic risks. When the financial system in Iceland broke down, depositor insurance meant nothing.
Another popular way of storing large amounts of money over long time, is to invest in real estate. Buy apartments in central Paris, London, New York. Very small risk that you lose anything, especially in real terms, if you can keep a cool head about when to sell. Downside is that these are not liquid assets.
Some hardcore asset management schemes store physical US bills in a high security storage. You will pay % negative yield on yearly storage cost, but cash is truly yours and you can withdraw any day.
Also in the EU, with some fintech startups, you can now open a bank account which comes with a IBAN number from a central bank of Lithuania - essentially your money is stored within European Central Bank system. You will have negative ECB interest and pay some extra, but there is no counterparty risk unless the whole European banking system collapses.