Owning fully segregated physical gold bars in secure vault storage in a stable jurisdiction is the most secure way to own gold.
ETFs may offer an easy way to invest in gold, but for long term wealth preservation the form in which you hold your gold will be of the upmost importance. ETFs do not offer physical gold storage, more likely part ownership of a larger gold bar that is co-owned by hundreds of other individuals and institutions.
If and when the global economy explodes into hyperinflation, how difficult might it be to claim ownership of your gold in such a situation! With this in mind, owning fully segregated gold bars with each bar serial number registered to your account, gives ultimate peace of mind in even the direst of economic circumstances.