Playa Arenillas
McBodes · CC BY 3.0 · Wikimedia Commons

Castro-Urdiales · Cantabria

Playa Arenillas

Swimming conditions, water quality, sea, tides and facilities

50 mSand
Water21 °CDaily high24 °CUV5High tide15:43Low tide21:50JellyfishNo recent observationsLess favourable conditions · estimate
Directions →
Swimming statusGreen flagEstimateForecast for 27/09 · 13:00Reference sea area: Playa Oriñon · 0.9 km

Now

Forecast for 13:00

AEMET · issued 27/09 09:05
☁
SkyHigh cloud
Temperature24 °CFeels like 24 °C
Forecast rain0%
Humidity57%
WindNE 6 km/hGusts 16 km/h
Water21 °C
Maximum UV5

This is an official forecast for the stated period, not an observation taken at the beach.

Environmental estimate

Conditions less favourable for jellyfish arrival

Forecast wind and the regional coastline orientation are less favourable for jellyfish transport towards the shore. This is a limited-confidence regional physical indicator; it does not confirm the presence or absence of jellyfish at this beach.

Accumulated wind4 km/h · 295°Valid for27/09/2026 13:00

Weather forecast

Hourly and daily outlook

Official municipal forecast and, where available, beach-specific information.

Next hours

Town of Castro-Urdiales
Today13:00☁24°High cloud☂ 0% · ↝ NE 6 km/h
Today16:00☁23°High cloud☂ 0% · ↝ N 11 km/h
Today19:00☁22°Mostly cloudy☂ 0% · ↝ NW 9 km/h
Today22:00☁20°Overcast☂ 40% · ↝ SW 4 km/h
Tomorrow01:00☁19°Overcast☂ 5% · ↝ S 5 km/h
Tomorrow04:00☁18°Overcast☂ 0% · ↝ S 3 km/h
Tomorrow07:00☁17°High cloud☂ 0% · ↝ E 1 km/h
Tomorrow10:00☁18°Overcast☂ 5% · ↝ E 5 km/h
Tomorrow13:00☁23°High cloud☂ 5% · ↝ NE 10 km/h
Tomorrow16:00☁23°Mostly cloudy☂ 10% · ↝ NE 6 km/h
Tomorrow19:00☁26°Overcast☂ 10% · ↝ N 4 km/h
Tomorrow22:00☁23°Overcast☂ 5% · ↝ S 5 km/h
Tuesday 2901:00◐22°Partly cloudy · ↝ S 15 km/h
Tuesday 2904:00☀21°Clear · ↝ SE 4 km/h
Tuesday 2907:00◐20°Partly cloudy · ↝ S 25 km/h

Today’s weather

At 13:00, the forecast indicates sky conditions of high cloud and a forecast temperature of 24 °C. This period also has a feels-like temperature of 24 °C, 0% chance of rain and wind NE at 6 km/h. For the day as a whole, the published forecast gives a high of 24 °C, water temperature around 21 °C and a maximum UV index of 5.

Next days

Today

☁

High cloud

Low 17°High 24°
☂ Rain 40% ↝ N · 2 km/h Gusts 22 km/h Humidity 57–92% ◉ Water 21° ☀ UV 5
Hourly municipal forecast · issued 27/09 09:05

Tomorrow

☁

High cloud

Low 17°High 26°
MorningHigh cloudAfternoonOvercast
☂ Rain 10% ↝ NE · 5 km/h Gusts 24 km/h Humidity 54–100% ◉ Water 21° ☀ UV 4
Hourly municipal forecast · issued 27/09 09:05

Tuesday 29

◐

Partly cloudy

Low 20°High 23°
☂ Rain 55% ↝ S · 20 km/h Gusts 46 km/h Humidity 52–65% ◉ Water 20° ☀ UV 5
Hourly municipal forecast · issued 27/09 09:05

Wednesday 30

☂

Mostly cloudy with rain

Low 17°High 25°
☂ Rain 100% ↝ N · 10 km/h Humidity 55–90% ☀ UV 5
Daily municipal forecast · issued 27/09 03:21

Water health

Water quality

NÁYADE source
Latest available test21/09/2026NÁYADE · Ministerio de Sanidad · ES13000020M39020B1
E. coli31 NMP/100 mL
Enterococci10 NMP/100 mL
Latest available annual classificationEXCELLENT2025 season · EEA · does not describe current conditions

The 2026 season does not yet have a final annual classification. The 2025 result is historical; for recent conditions, check the latest test and any published incidents.

View all test results
DateAssessmentE. coliEnterococci
21/09/2026Suitable for bathing31 NMP/100 mL10 NMP/100 mL
31/08/2026Suitable for bathing10 NMP/100 mL10 NMP/100 mL
17/08/202620 /08/2026—
03/08/2026Suitable for bathing64 NMP/100 mL31 NMP/100 mL
15/07/2026Suitable for bathing87 NMP/100 mL31 NMP/100 mL
02/07/2026Suitable for bathing20 NMP/100 mL10 NMP/100 mL
15/06/2026Suitable for bathing64 NMP/100 mL20 NMP/100 mL
01/06/2026Suitable for bathing20 NMP/100 mL10 NMP/100 mL
19/05/2026Suitable for bathing53 NMP/100 mL10 NMP/100 mL
08/09/2025Suitable for bathing10 NMP/100 mL10 NMP/100 mL
27/08/2025Suitable for bathing53 NMP/100 mL10 NMP/100 mL
11/08/2025Suitable for bathing87 NMP/100 mL10 NMP/100 mL
14/07/2025Suitable for bathing160 NMP/100 mL20 NMP/100 mL
23/06/2025Suitable for bathing10 NMP/100 mL75 NMP/100 mL
02/06/2025Suitable for bathing10 NMP/100 mL31 NMP/100 mL
30/09/2024Suitable for bathing10 NMP/100 mL10 NMP/100 mL
16/09/2024Suitable for bathing178 NMP/100 mL31 NMP/100 mL
02/09/2024Suitable for bathing137 NMP/100 mL178 NMP/100 mL
19/08/2024Suitable for bathing20 NMP/100 mL10 NMP/100 mL
29/07/2024Suitable for bathing75 NMP/100 mL10 NMP/100 mL
08/07/2024Suitable for bathing10 NMP/100 mL10 NMP/100 mL
24/06/2024Suitable for bathing10 NMP/100 mL10 NMP/100 mL
10/06/2024Suitable for bathing10 NMP/100 mL87 NMP/100 mL
27/05/2024Suitable for bathing10 NMP/100 mL20 NMP/100 mL
25/09/2023Suitable for bathing10 NMP/100 mL10 NMP/100 mL
11/09/2023Suitable for bathing64 NMP/100 mL20 NMP/100 mL
31/08/2023Suitable for bathing124 NMP/100 mL75 NMP/100 mL
07/08/2023Suitable for bathing20 NMP/100 mL10 NMP/100 mL
17/07/2023Suitable for bathing42 NMP/100 mL10 NMP/100 mL
03/07/2023Suitable for bathing164 NMP/100 mL20 NMP/100 mL
View annual history
2025 EXCELLENT EEA2024 EXCELLENT EEA2023 EXCELLENT EEA2022 EXCELLENT EEA2021 EXCELLENT EEA2020 EXCELLENT EEA2019 EXCELLENT EEA2018 EXCELLENT EEA2017 EXCELLENT EEA2016 GOOD EEA2015 GOOD EEA

A sample or annual classification does not override a later incident or operational flag.

Water quality

The latest microbiological sample was taken on 21/09/2026. The available annual classification for 2025 is excellent; this is a historical assessment, not confirmation of today’s conditions.

Beach at a glance

What it is like

Characteristics published by official sources

Playa Arenillas, also known as Islares, is a small beach 50 metres long and 15 metres wide, with fine golden sand and a mountain setting. Its calm waters, moderate occupancy and the low tourist attendance described in the record define a sheltered space, also integrated into the Montaña Oriental PORN. An anchorage area is also recorded. Access is easy on foot from the CN-634, with fewer than 50 parking spaces and an interurban bus between Santander and Castro-Urdiales. There are showers, food, cleaning and an area for surfing.

Length50 mApproximate size of the beach
Typical width15 mPublished average width
CompositionSandPredominant material
Sand typeGoldenPublished texture or colour
SettingSemi-urbanLevel of development
Coastal settingMountainSurrounding landscape
Access typeEasy on footPublished access options
Available characteristicProtected area

Available facilities

Facilities

Only facilities published as available are shown
WC
Showers
Bins
Cleaning service
Food and drink
Surfing area
Anchorage
MarinaCastro Urdiales

Facilities and comfort

Confirmed facilities include toilets, showers, bins, a cleaning service and food and drink.

Activities

Published information identifies a surfing area, an anchorage and the nearby Castro Urdiales marina.

Access and safety

Accessibility and safety

Accessibility and transport

✓
ParkingFewer than 50 spaces
✓
BusIntercity bus, Santander - Castro Urdiales

Safety and assistance

⚑
LifeguardsLifeguard staff and equipment · Emergency number 112
+
First aidPublished first-aid post
!
Safety signageOfficial beach safety signage
+
Nearest health facilityHospital Comarcal de Laredo · 20 km

Access and accessibility

Travel options include parking, a bus connection and access from CN-634.

Location

Directions

Open directions in Google Maps

Practical ideas for your visit

Near this beach

Eat, have a drink, stay or park nearby without spending time searching.

About these results: distances are calculated in a straight line and each link opens the stored point, rather than a name search. Position does not imply an editorial recommendation or guarantee opening times or availability.

A few kilometres away

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