A 91-year-old peace activist has crossed Ireland on foot and arrived in Dublin to petition the government to bar US military flights.

Lelia Doolan completed a two-week, 220km trek on Wednesday, ending at the gates of parliament accompanied by throngs of supporters.

The film producer and activist made the journey to protest against the US military’s use of Shannon airport in County Clare. “US military planes are landing without anybody ever agreeing in government to search them or see what’s in them. Shannon is a civilian airport. It’s not a military airport.”

US personnel with sidearms pass through Shannon but the government says the airport is not used in US combat operations and that there is no evidence that weapons and supplies for US attacks enter Irish airspace.

Doolan, however, said the agreement to permit some US military flights violated Irish neutrality and that people had been “fooled” into thinking the practice had to continue. “It doesn’t have to continue.”

She started from the airport on 31 March and met supporters in Limerick, Nenagh, Roscrea, Portlaoise, Newbridge, Naas and other stops on her way to the capital, covering most but not all of the distance on foot.

Activists have for decades protested against the agreement that lets US military aircraft refuel at Ireland’s second-biggest airport, on the west coast.

The conflict in the Middle East has galvanised fresh action, including an incident last week when a suspect in his 40s was arrested after allegedly damaging a US air force C-130 Hercules transport aircraft that was parked on a remote taxiway.

Controversy over US military flights has spread throughout Europe, including Italy, which last month denied the use of an airbase in Sicily.

Doolan said she felt a duty to protest against the traffic of US military personnel through Ireland and to avow Irish neutrality. It did not take much for a woman to be considered “troublesome”, she said. “That’s why there is so many of us”. She exhorted those who wished to make a difference to act on the impulse. “It’s very simple. Just do it.”

Supporters joined Doolan, who turns 92 next month, for sections of the “walk with Lelia” campaign. The journey, which was also in memory of Doolan’s late friend and fellow campaigner Margaretta D’Arcy, included traditional music sessions.

Hugs, cheers, Palestinian flags and opposition politicians greeted Doolan when she reached Leinster House, which hosts the Dáil and Seanad chambers of parliament.

Doolan – who celebrated her 90th birthday with a skydive – paid tribute to those she met during the walk. “If you only knew how wonderful the people of Ireland are. If only you knew how engaging they are, decent and intelligent they are.” She read a poem titled Kindness, by Naomi Shihab Nye, and joined supporters in a peace song.

In the Dáil, Ivana Bacik, the leader of the Labour party, praised Doolan and urged the government to cease letting US military planes use Shannon.

The taoiseach, Micheál Martin, expressed respect for Doolan and said he would try to meet her, but said the airport had no role in the Middle East conflict. “We need to be very careful that we don’t miscategorise Shannon airport. I think that will damage Shannon airport.”