Conversation so far:
who owns the gold in the bank of england
The Bank of England stores the UK’s gold reserves on behalf of HM Treasury / UK government.
Who owns the gold in the Bundesbank?
Ownership of Germany’s gold reserves resides with the German State and the Deutsche Bundesbank officially acts on behalf of the German State.

Question: which country's bank has the most gold in the world
Self-contained rewrite: Which bank has the most gold reserves?