He's raised nearly €100,000 for his charity after undertaking the journey.
Bressie says he's been hit with a wave of exhaustion after kayaking the length of the Shannon.
Niall Breslin has raised almost €100,000 for his charity Lust for Life by undertaking the 300km trek over seven days.
He says while the challenge was difficult, it's nothing compared to the struggle parents have when they are looking for mental health services for their children.
Niall Breslin has been speaking to Sinéad Hubble on Midlands Today, and says the river and lakes are a metaphor for life:
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