For runners chasing a 5K PB, Ireland offers a range of fast, flat courses that can help you bag that elusive time. Whether you’re a seasoned speedster or a beginner aiming to set a benchmark, a flat 5K minimises elevation challenges, letting you focus on pace and performance. Here are five of the best flat 5K races in Ireland for 2025, perfect for pushing your limits and achieving that goal.
1. Lifestyle Sports Parkwest 5km – Parkwest Business Park, Dublin
The Parkwest Dublin Night Run race starts just down from the Park West Plaza and brings runners on a flat route around the Business Park and along Dublin's Grand Canal, with participants completing one full loop.
- Why it’s PB-friendly: Flat course around the Business Park.
- When: July 22nd, 2025 at 7:20 PM.
- Location: Parkwest Business Park, Dublin
- Entry: Approx €28.50.
2. Rathfarnham 5K – Rathfarnham, Dublin
The Rathfarnham 5k is a fast downhill course along the banks of the River Dodder, starting on Springfield Avenue, making it a rewarding choice for PB chasers. The race was a sellout in 2024, so make sure to get your entry in early.
- Why it’s PB-friendly: Fast, flat, downhill course with only 52ft of elevation.
- When: September 28th, 2025 at 9:30 AM.
- Location: Rathfarnham, Dublin
- Entry: Approx €25.
3. Docklands 5K – Dublin Docklands
Organised by Crusaders Athletic Club, the Docklands 5K is a non-profit event held in Dublin’s vibrant Docklands area. The flat, fast loop starts near the Samuel Beckett Bridge, crosses the Matt Talbot Bridge, and finishes along Sir John Rogerson’s Quay. With a course designed for speed, it’s a go-to for runners aiming to clock a personal best. Pacers for 20, 25, and 30-minute finishes help you hit your target time, and the evening start adds a unique energy to the race.
- Why it’s PB-friendly: Flat, accurately measured course with pacing groups to keep you on track.
- When: July 10, 2025, at 8:00 PM.
- Location: Dublin Docklands, Co. Dublin.
- Entry: €25 for individuals, €75 for teams of three.
4. Night Of The 5k PBs - Arklow, Wicklow
A new entry to the racing calendar is Coral Leisure Arklow with its first ever Night Of The 5k PBs charity run in aid of Arklow Community First Responders. This event will be run on a fast, flat looped course with pacers provided. There will be 2 events on the night, consisting of a paced 5k race for sub-30 minutes down to sub-20 minutes, which will also be open to recreational runners and walkers, and an elite 5k race will be held at 7.30 pm.
- Why it’s PB-friendly: The clue is in the name here. A fast, flat looped course with pacers.
- When: July 19th, 2025, at 7:00 PM.
- Location: Arklow, Wicklow.
- Entry: Approx €21.40.
5. Celbridge 5k Road Race – Cellbridge, Kildare
The annual Cellbridge 5k Road Race, organised by Celbridge AC promises a great night's racing starting and finishing at the club on a flat and fast course. There's a free race T-shirt for the first 250 entries, and a fantastic after-race atmosphere with great prizes
- Why it’s PB-friendly: Flat, fast course with great atmosphere.
- When: August 21st, 2025, at 8:00 PM.
- Location: Cellbridge, Kildare
- Entry: Approx €20.
Tips for Nailing Your 5K PB
- Choose the Right Shoes: Opt for lightweight racing shoes.
- Pace Yourself: Use pacers where available or practice your goal pace in training to avoid going out too fast.
- Train Smart: Incorporate interval training and tempo runs into your schedule to build speed and endurance.
- Check the Course: Familiarise yourself with the route map to anticipate turns and plan your effort distribution.
- Warm Up Properly: A dynamic warm-up can prime your muscles for peak performance on race day.
Ready to lace up and set a new personal best? Sign up for one of these flat 5K races and hit the ground running in 2025!