This week I visited Arundells, a beautiful house opposite Salisbury Cathedral which the late Sir Edward Heath left to a trust so that it could be open to the public.
The former Prime Minister will be remembered for many things, but a key event of his premiership was Britain joining what was then the European Economic Community in 1973, a decision endorsed in a referendum two years later.
What began in the 1950s as the European Coal and Steel Community, with six members, has now become a European Union of 27 nations. Of these, 17 have adopted the single currency, the euro.
When the euro was being formed over a decade ago, I led the national campaign which successfully argued that Britain should not join. We believed that membership would damage our economy, removing crucial flexibility through the ability to set our own monetary policy. Events have proved us right.
At the time, British politicians who wanted to give up our currency claimed that it would not necessitate greater economic integration with other euro countries. But as I pointed out, there has never been a successful currency union in history without the economic and political union to back it up.
Today we see huge pressure on the economies of Portugal, Ireland and Greece, necessitating a massive commitment of billions of euros by Eurozone countries in order to keep the single currency intact.
Fortunately Britain is not footing the latest bill, but there is growing resistance from taxpayers in recession-hit EU countries at having to do so, while public support for joining the euro in countries like the Czech Republic has collapsed.
There is little doubt that the expansion of the Eurozone's bail-out fund is another step on the road to further fiscal integration. As the Chancellor of the Exchequer argued last week, this is "the inexorable economic logic of a single currency."
Some European politicians, such as the former Prime Minister of Spain, José María Aznar, argue against a European finance ministry or tighter fiscal union which would lead to the "undesirable political division of Europe". They believe that the single currency can still succeed through budgetary discipline and reform to liberalise Europe's economies.
But for many of Europe's leaders, deeper integration is now more urgent to ensure the euro's long term survival. Stefan Collignon, a German professor of economic policy, said last week: "The solution is to advance towards political union with the establishment of real European economic government."
Werner Hoyer, Germany's Europe Minister, called for "more Europe, not less", with "further steps towards integration and political union."
It is not in Britain's interests for the euro to collapse. The economic impact on our economy, as we struggle to regain growth, would be extremely damaging.
Nor do I argue that we should turn our backs on membership of the wider European Union and the single market which is so beneficial to business.
But if a euro core emerges, where nations cede control not just of interest rates but key elements of economic policy and taxation, too, I do not believe that the British public would accept being a part of it.