McAlpine's Fusiliers are back and buying up Britain

Over a hundred years ago the brawn of, mostly, Irish navvies helped build modern-day Britain, constructing the canals and forming the railways which allowed the country to steam its way to industrial grandeur. Fifty years ago, they were still coming in such numbers to build the post-war motorways and housing estates, that they became known as McAlpine's Fusiliers.

Now their prosperous descendants are back - and they are buying up large swaths of the country they helped create.

Ambitious and expansionist Irish property speculators and entrepreneurs have moved into Britain in a big way, acquiring major enterprises. According to one report, Ireland has surpassed the United States as the single biggest outside investor in British commercial property, with more than 20 per cent of overseas purchases last year.

Irish financial investment in Britain is zooming ahead by the billion. And, in a new twist, well-known money-men from the Republic of Ireland have been joined by lower-profile investors from Northern Ireland.

An international Irish spending spree has already netted landmark London hotels such as Claridge's, the Connaught, and the Berkeley, in addition to large slices of real estate and retail developments.

While estimates vary, it seems likely that the southern Irish own more than €17bn (£11.75 bn) worth of commercial property in the UK, with some of Ireland's richest men amassing very large investment portfolios. An Irish-owned company is heavily involved in a huge plan to transform Liverpool's city centre, while others are pouring money into Luton, Glasgow and Manchester.

At the same time, tens of thousands of cash-rich Irish families are buying second homes or investment properties abroad, in locations as far-flung as South America.

But the high-spending southerners are being joined by Northern Irish entrepreneurs who made their fortune in Belfast during the Troubles.

A dozen or more Belfast-based developers have become substantial players in retail investment, buying shopping centres, retail parks and high street property.

Keith Shiells, of the Belfast property consultancy BTWShiells, said: "On behalf of clients, this company has spent about £2bn in Britain in recent years. There are 12 to 15 heavy hitters, either individuals or partnerships."

One bought a Leicester retail park for £360m, while another spent £250m on a large Doncaster shopping centre - moves which, in the property market jargon, are known as "buying really chunky". Mr Shiells said: "Most of them have a good core business, such as house building or the licensed trade, and the property has derived from that. They're all very low key. They don't have a big corporate profile, they tend to like to keep their head below the parapet."

On a smaller scale, the surge in Irish prosperity has brought an extraordinary wave of property buying at a lower level, with an unusually high proportion of families owning two homes.

Many such houses and apartments are in the Irish Republic, particularly in coastal districts. But the traditional Irish passion for property has resulted in thousands of purchases in Britain, as well as in traditional holiday destinations.

More recently, however, Irish buyers have shown a huge taste for new venues, with Bulgaria now a firm favourite for holiday homes. Such investments have been facilitated by a growth in new destinations served by Irish airlines.

The more adventurous property buyers are venturning much further afield, apparently vying with each other in finding the most unusual and unexpected destinations.

Some are buying in Brazil, while recent advertisements have appeared in Irish newspapers offering perhaps the most exotic yet: apartments in Borneo.