Thousands of holidaymakers passed through Irish airports as travel restrictions in and out of the country were lifted on Monday.
Ireland has implemented the EU Covid Certificate, allowing people who are fully vaccinated to travel freely.
The certificate has been in place in other EU countries since July 1.
The lifting of restrictions on travel saw thousands of people going on holidays while others travelled back to Ireland to visit family and friends.
It is now possible to travel to Ireland from countries within the EU, Iceland, Lichtenstein, Norway and Switzerland with no requirement to quarantine if the traveller has valid proof of being fully vaccinated, having recovered from Covid-19 or have had a negative PCR test in the last 72 hours.
Mark Mills, from Letterkenny in Co Donegal, was travelling to Bordeaux in France to visit family members.
He received his EU Digital Certificate in an email.
“We just had to apply it to the Covid tracker so we now have it nice and easy on our phones,” he said.
“We are on our way to Bordeaux. We originally booked with Ryanair but that was cancelled.
“We rebooked with Aer Lingus and that was cancelled as well and eventually got on to KLM to travel through Amsterdam and then on to France.
“It’s going to be great. We are going to see our family.”
Mr Mills, who has been working from home since the pandemic, said he has missed seeing family and friends.
He is travelling with his wife Isabelle and daughter Kira.
Isabelle received the EU certificate on Monday, a process she said was “very fast”.
Kira received a negative PCR test before she was allowed to travel.
“The test isn’t pleasant but it was fast,” she added.
Sisters Maya, Ciara and Sinead Olonargian travelled to Munich to visit family.
Maya said they had been looking forward to a holiday after a “boring” six months in lockdown.
They received their EU Digital Certificate after undergoing PCR tests.
Maya said: “I got my vaccination, but it was too late to travel on.
“There are too many people who want the vaccine but not enough supply.”
Sinead said: “It has been almost two years since I was on an airplane. We are are excited to see our family, and our granny.”
DAA (Dublin Airport Authority) chief executive Dalton Philips said: “We have been waiting patiently for international travel to resume and it is wonderful to see customers coming through the doors of our terminals again for leisure and business travel.
“There is a great buzz and air of excited anticipation at our airports.
“We have missed our passengers, our airlines have missed them and our business partners have missed them.”
Covid-19 has had a crippling effect on every aspect of the travel and tourism sector.
“Dublin and Cork Airports have experienced a loss of over 43 million passengers in the past 16 months,” Mr Philips added.
“We are working tirelessly to restore the vital connectivity that Ireland has lost during that time.”
Passengers have been advised to arrive at the airport at least two hours for European flights, and three hours for US travel.
It comes as nearly 80% of the adult population have received a first dose of Covid-19 vaccine.