The interest from airports and airlines was intense and last December it was announced that the ARD fund was being wound up, with Enterprise Minister Maria Eagle concluding that it had been a job well done.

At its launch there was just one international scheduled service from Northern Ireland – the Belfast International to Amsterdam route.

But now the number of destinations served by scheduled services has mushroomed, and the list continues to lengthen.

Not all the new routes owe their origins to support offered by the ARD fund, but there is no doubt that under the chairmanship of businessman Bill McGinnis, it set the wheels in motion.

The no-frills carriers were not slow to see the scope for expansion, with easyJet, jet2.com and Wizz Air joining the fray.

The ARD fund was primarily aimed at developing routes of interest to the business community along with those which would produce inbound tourism for Northern Ireland.

While the initiative has paid dividends on both scores, it has also opened up a whole new world for the people of Northern Ireland, who have suddenly taken wing.

The growth has been exponential. This summer no fewer than 42 destinations will be served by direct flights from Belfast International, and 21 from George Best Belfast City.

The Aldergrove list now includes five cities in North America and 20 on the Continent, the newest being the soon to be launched Polish services – to Katowice, Krakow and Warsaw.

City Airport has got in on the act with Flybe establishing a link between Belfast and Rennes in France ,which is due to start at the end of May.

For the airlines and the airports the only way is up, and scheduled services are augmented by an array of summer and winter charter flights.

Passenger numbers at Aldergrove hit five million in 2006, up from 4.8 million in 2005, while Belfast City held its own, although its 2.1 million total was slightly down on the previous year.

The rise was most dramatic at City of Derry Airport, where passenger numbers rose from 205,821 in 2005 to 348,481 last year, due to the the reinstatement of the second Ryanair daily flight to London Stansted and new routes to Liverpool, Nottingham and Prestwick.

Both Belfast airports are now controlled by Spanish companies – infrastructure giant Ferrovial owns City Airport and toll road operator Abertis is parent to Belfast International.

And while passenger numbers have been growing, developments have took place on the ground. Last summer Belfast International launched a 2030 masterplan which envisaged an increase in passenger traffic from the present level to 10–12 million over the next 25 years.

The first phase of the proposed investment of £60m over 10 years will involve an expansion of the check-in area and the relocation of the current search area to increase airside retail space, while there are plans to improve car parking with the construction of a multi-storey facility.

BIA is also making a pitch for increased business from south of the border, and the airport management believes it is possible that passenger numbers from the Republic can be increased from their present level of 100,000 to around 250,000 within a few years.

Passenger numbers at Dublin Airport hit 21 million last year, a 15% increase over 2005, but the downside is that the terminal suffers from major congestion at peak periods.

Plans are in hand, though, for a €2bn (£1.35bn) expansion which will see a new departures facility and a new terminal, which is due to be ready by 2009 and which will increase capacity to 35 million a year.

Improved roads and the choice of destinations make Dublin attractive, but Belfast’s airports are hoping that the upgraded road link will win them business from the Republic.

Growth at Belfast City is still hampered by the planning consent. But the rules were relaxed last December when the Department of the Environment published the outcome of the Planning Service’s Examination in Public (EiP).

It recommended that the limit on seats for sale should be raised from 1.5 million to two million a year, outbound and inbound. It also decreed that the existing limit of 45,000 aircraft movements per annum remain in force.

But despite calls by Flybe and bmi for the night-time curfew to be pushed back slightly, the panel recommended that the existing 9.30pm shutdown remain in force. Indeed it suggested that fines of up to £800 a time should apply to delayed flights which disturbed the peace of nearby residential areas. The challenge is to strike a balance between the social and economic benefits of having an airport near the city centre and the downside of noise for local people. To this end the EiP made it a condition of the relaxation that City Airport should install sophisticated noise monitoring and management systems.

But it is not just the airports which are looking to the future. Next April ferry company Stena Line relocates its HSS operation to a new £35m terminal at the seaward end of the Port of Belfast. The new facility, coupled with a relocation from Stranraer to Cairnryan at the Scottish end, will reduce journey times by 20 minutes.

The ferry operator insists that it is geared up to meet the challenge of the no-frills airlines. Gunnar Blomdahl, Stena Line’s global chief executive officer, says the company has continued to grow on its Irish Sea routes and is in the midst of a £150m investment in the service from Belfast.

The ferry companies say they score over the airlines because of their reduced check-in times and their ability to take luggage without charging extra for every kg over the limit.

But the bedrock will always be freight and the ferry services, which provide an economic lifeline for Northern Ireland. Whether getting exports to market, imports to customers or people to meetings, Ulster’s air and sea links are proving to be more important than ever in the 21st century.