Poolbeg Lighthouse, Co Dublin
Poolbeg Lighthouse, Co Dublin Courtesy Cathy Wheatley, Carol Wheatley

Half Moon Bay

📍 Dublin, Dublin

🏛️ Attraction

Last updated: 28 April 2026

Overview

Poolbeg Lighthouse at Night, Co Dublin
Poolbeg Lighthouse at Night, Co Dublin Courtesy Riccardo Rea

Half Moon Bay is a unique urban swimming location tucked away on the Great South Wall, midway along the south‑side of Dublin Bay. Though it is not a traditional sandy beach, the site provides a ladder‑ or slipway‑accessed bathing platform that drops directly into the Irish Sea. The water is monitored by the Environmental Protection Agency and has earned an Excellent rating for the past four years (2021‑2024). The bay is framed by the Great South Wall to the north and the open sea to the south, creating a narrow, sheltered stretch that is especially popular with sea‑swimmers, water‑polo enthusiasts, and anyone looking for a quick dip after a city stroll.

The area forms part of the South Dublin Bay and River Tolka Estuary Special Protection Area (SPA), the South Dublin Bay Proposed Natural Heritage Area, and the South Dublin Bay Special Area of Conservation (SAC). These designations protect a range of water‑fowl, including the internationally important Light‑bellied Brent Geese, and nine other nationally significant species. The proximity to Sean Moore Park and the Irishtown Nature Reserve adds a touch of green to the otherwise maritime setting.

History

The Great South Wall was constructed in the early 19th century to protect Dublin Port from silting and to provide a safe anchorage for ships. In the 1970s a concrete platform was added at the wall’s midpoint, creating the present‑day Half Moon Bay swimming area. The platform has since become a focal point for local water‑polo clubs and open‑water swimmers, while the surrounding SPA status, introduced in the 1990s, safeguards the important bird populations that winter here.

What to See & Do

Poolbeg Lighthouse at Night, Co Dublin
Poolbeg Lighthouse at Night, Co Dublin Courtesy Riccardo Rea
  • Swimming & Water Polo – The Half Moon Swimming & Water Polo Club operates a modest shelter and changing facilities right on the wall. Whether you are joining a club session or simply taking a solo plunge, the calm waters are ideal for both beginners and seasoned swimmers.
  • Wildlife Watching – Birdwatchers will appreciate the regular passage of migratory geese and other water‑fowl that use the SPA for feeding and roosting. Early mornings often bring flocks of Brent Geese, while winter months see a variety of ducks and waders.
  • Scenic Walks – The Great South Wall itself is a popular promenade for walkers and cyclists. From the Half Moon platform you can enjoy uninterrupted views of Dublin Port, the iconic Poolbeg Lighthouse, and the rolling horizon of the Irish Sea.
  • Tide & Weather Checks – Before heading out, consult the Dublin Port Company public notices for any temporary closures due to adverse weather. The UK & Ireland Beaches app also provides up‑to‑date tide times and marine forecasts.

Practical Information

Half Moon Bay is free to access and open year‑round, though swimming is only permitted when conditions are safe. Access is pedestrian‑only along the Great South Wall; bicycles are allowed on the designated path but must stay on the lane. Vehicle access is limited to emergency services and a small car park at the wall’s entrance – visitors are encouraged to use the nearby Shelley Banks car and bicycle parking to avoid congestion and protect the sand dunes.

FeatureDetails
Water QualityExcellent (2021‑2024)
AccessLadder or slipway from Great South Wall; foot or bicycle only
FacilitiesChanging shelter, water‑polo club amenities
Safety NoticesIssued by Dublin Port Company during adverse weather
ParkingShelley Banks car & bike bays (recommended)

Getting there

  • By car – Follow signs to the Great South Wall from the Dublin Port area; use the Shelley Banks parking area.
  • By public transport – The nearest DART stations are Connolly and Pearse, followed by a short bus or taxi ride to the wall entrance.
  • By bike – Dedicated cycle lanes run along the wall, making it a pleasant ride from the city centre.

When to visit

The water remains cool year‑round, but the summer months (June‑August) see the highest number of swimmers. Autumn brings striking colours along the shoreline, while winter offers the best chance to spot migratory geese.

Contact & Further Info

Enjoy the blend of urban convenience and natural beauty that makes Half Moon Bay a standout spot for a quick swim, a paddle, or simply a breath of sea‑air in the heart of Dublin.