Sea
Salt water, tidal range and swell. Temperature lags the seasons by six to eight weeks, peaking in late August.
| Spot | Type | Region | Max depth | Walk | January | August |
|---|---|---|---|---|---|---|
| Pomena, Mljet A small harbour on the wooded island of Mljet where the sea reaches 25 °C in August and the swim out to the islet of Pomestak takes 12 minutes. |
Sea | Dalmatia, Croatia | 22 m | 1 min | 13.5° | 25° |
| The Forty Foot, Sandycove A granite bathing place at the tip of a Dublin headland, swum from year-round since 1740, immortalised in Ulysses, and still the benchmark for cold-water swimming in Ireland. |
Sea | County Dublin, Ireland | 6 m | 8 min | 9° | 16° |
| Bude Sea Pool A 91 m tidal pool cut into the rocks below Summerleaze Down in 1930 — filled by every high tide, sheltered from the Atlantic swell, and free to use. |
Sea | Cornwall, England | 3.4 m | 5 min | 9° | 17° |
Before you get in
Cold water is the one hazard that applies everywhere in this library. Below 15 °C the gasp reflex can make you inhale water involuntarily within seconds of immersion; below 10 °C, unacclimatised swimmers lose the ability to swim effectively within minutes. Enter gradually, keep your first session under five minutes, never swim alone, and get out while you still feel fine — the afterdrop continues after you leave the water.