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Cardiff · December · relief from the heat

Coolest places to go from Cardiff in December

In December, the coolest well-known place within 15 hours of Cardiff is Rovaniemi, Finland, 15.5 °C cooler than Cardiff and 0.1 h sun a day, about 6h 36m each way by air. Without flying, it is La Chaux-de-Fonds, Switzerland, 6.7 °C cooler than Cardiff, about 13h 48m each way by train, for about 15× less carbon (37.7 kg CO₂e return against 581 kg).

The 10 coolest places within 15 hours of Cardiff

Ranked on relief from the heat in December alone, among well-known places (a Wikivoyage travel guide and at least 40,000 Wikipedia readers a year), one per area and at most three per country. The carbon is shown, not used to choose: the list further down is the other question, how much relief from the heat each extra kilogram buys.

  1. Rovaniemi, Finland15.5 °C cooler · 0.1 h sun a day · 1.2 mm rain a dayair ≈ 6h 36m · 581 kg CO₂e return
  2. Tromsø, Norway13.7 °C cooler · 0.0 h sun a day · 3.8 mm rain a dayair ≈ 6h 36m · 585 kg CO₂e return
  3. Joensuu, Finland13.6 °C cooler · 0.9 h sun a day · 1.7 mm rain a dayair ≈ 6h 36m · 580 kg CO₂e return
  4. Östersund, Sweden13.5 °C cooler · 0.9 h sun a day · 1.8 mm rain a dayair ≈ 5h 42m · 421 kg CO₂e return
  5. Oulu, Finland13.4 °C cooler · 0.4 h sun a day · mostly dry · sea 0.2 °Cair ≈ 6h 30m · 558 kg CO₂e return
  6. Luleå, Sweden13.1 °C cooler · 0.3 h sun a day · 1.9 mm rain a day · sea 0.8 °Cair ≈ 6h 18m · 534 kg CO₂e return
  7. Umeå, Sweden12.8 °C cooler · 0.9 h sun a day · 2.1 mm rain a day · sea 2.0 °Cair ≈ 6h 6m · 487 kg CO₂e return
  8. Bodø, Norway11.8 °C cooler · 0.0 h sun a day · 7.8 mm rain a day · sea 6.7 °Cair ≈ 6h 12m · 504 kg CO₂e return
  9. Oslo, Norway10.5 °C cooler · 1.8 h sun a day · 1.7 mm rain a dayair ≈ 5h 12m · 321 kg CO₂e return
  10. Erzurum, Turkey10.5 °C cooler · 6.9 h sun a day · mostly dryair ≈ 8h 18m · 910 kg CO₂e return

Without flying

The coolest places the train reaches within 15 hours. La Chaux-de-Fonds is 6.7 °C cooler for 37.7 kg — about 15× less carbon than flying to Rovaniemi.

  1. La Chaux-de-Fonds, Switzerland6.7 °C cooler · 4.0 h sun a day · 5.1 mm rain a dayrail ≈ 13h 48m · 37.7 kg CO₂e return
  2. Suhl, Germany6.3 °C cooler · 1.8 h sun a day · 3.7 mm rain a dayrail ≈ 14h 24m · 39.5 kg CO₂e return
  3. Bern, Switzerland5.9 °C cooler · 4.8 h sun a day · 4.8 mm rain a dayrail ≈ 13h 48m · 39.0 kg CO₂e return
  4. Memmingen, Germany5.9 °C cooler · 4.2 h sun a day · 3.5 mm rain a dayrail ≈ 14h 36m · 41.7 kg CO₂e return
  5. Ulm, Germany5.8 °C cooler · 3.9 h sun a day · 2.7 mm rain a dayrail ≈ 14h · 40.6 kg CO₂e return
  6. Zurich, Switzerland5.3 °C cooler · 4.1 h sun a day · 4.6 mm rain a dayrail ≈ 13h 12m · 39.9 kg CO₂e return

≈ is the model's estimate (air times include getting to and through the airport); ✓ is a rail journey checked against a real timetable, with the date it was checked. Temperatures are historical daily means for 2023–2024, averaged across day and night, so afternoons run warmer.

The low-carbon trade-off

The coolest place you can reach from Cardiff in December within 15 hours is Rovaniemi, 15.5 °C cooler, costing 581 kg CO₂e return. The lowest-carbon option is Buxton at 17.3 kg — 34× less carbon, for 12.7 degrees less relief from the heat.

Every destination here is on the efficiency frontier: nowhere else this site covers is both cooler in December and lower in carbon. Anything a better option beats outright has been left out.

BuxtonRovaniemi
Where they are. Solid lines are rail or ferry, dashed are flights, from Cardiff. Pick one to compare.
Carbon against relief from the heat, December, departing Cardiff. Journeys of up to 15 hours each way.10 destinations. Lowest carbon Buxton at 17.3 kilograms and 2.8 °C cooler; best for relief from the heat Rovaniemi at 581 kilograms and 15.5 °C cooler. Buxton · 17.3 kgLillehammer · 341 kgTornio · 557 kgRovaniemi · 581 kg

By rail or ferry By air

Carbon against relief from the heat, December, departing Cardiff. Journeys of up to 15 hours each way.

What the 15-hour limit costs: at this budget Drammen can only be reached by air — 312 kg CO₂e, in 5h 12m. Allow up to 24 hours and the train does the same journey for 50.0 kg in 23h 12m — 6× less carbon for 18h more travelling.

December from Cardiff — 10 destinations on the frontier, 5 without flying.
DestinationHowCO₂e returnTempSun/dayRain/dayJourney
Buxton, United KingdomRail17.3 kg4.9 °C2.0 h4.6 mm4h 36m
Arlon, BelgiumRail30.7 kg3.6 °C1.8 h3.0 mm10h 24m
Schmallenberg, GermanyRail34.3 kg2.8 °C1.6 h4.6 mm12h 18m
Freudenstadt, GermanyRail37.6 kg1.8 °C3.1 h4.4 mm12h 48m
La Chaux-de-Fonds, SwitzerlandRail37.7 kg1.0 °C4.0 h5.1 mm13h 48m
Porsgrunn, NorwayAir295 kg-1.8 °C2.3 h3.2 mm5h 6m
Drammen, NorwayAir312 kg-3.4 °C2.1 h2.8 mm5h 12m
Lillehammer, NorwayAir341 kg-6.0 °C1.9 h1.9 mm5h 18m
Tornio, FinlandAir557 kg-7.0 °C0.1 h1.4 mm6h 30m
Rovaniemi, FinlandAir581 kg-7.8 °C0.1 h1.2 mm6h 36m

Warm is not the same as pleasant, which is why sunshine and rainfall are shown alongside temperature. All three are ERA5 monthly means for 2023–2024.

Where the curve breaks

The frontier is gentle until it isn't. Going from Lillehammer (341 kg, 13.7 °C cooler) to Tornio (557 kg, 14.7 °C cooler) buys 1.0 °C more relief from the heat for an extra 215 kg — 215 kg of CO₂e per degree. That single step is the most expensive relief from the heat on the whole curve.

The pick of them

Buxton, United KingdomBuxtonUnited Kingdom17.3 kg CO₂e return4.9 °C · 2.0 h sun · 4h 36m by railgrey and wetLa Chaux-de-FondsSwitzerland37.7 kg CO₂e return1.0 °C · 4.0 h sun · 13h 48m by railcoolRovaniemiFinland581 kg CO₂e return-7.8 °C · 0.1 h sun · 6h 36m by aircool

The same month, asked differently

December answers differently depending on what you are after, and the lists genuinely diverge: the brightest places are not the hottest, and in summer the useful question stops being where is warm at all.

Where to stay in Rovaniemi

Places to stay in Rovaniemi, Finland, on a live map. Prices and availability come from Stay22 and its booking partners.

Search places to stay in Rovaniemi →Opens the booking search in a new tab. Same partners as the map below.

Affiliate disclosure. A booking made through this map may earn 0xCarbon a commission, at no extra cost to you. It changes nothing above it: the emissions figures come from UK Government conversion factors and are computed before anyone is paid anything.See the method.

Other months from Cardiff

December from elsewhere

Photo credits

Questions

Where is the coolest place to go from Cardiff in December?

Rovaniemi, Finland, at 15.5 °C cooler. Reaching it emits 581 kg CO₂e return, travelling 6h 36m each way by air (modelled).

Can I get somewhere cool from Cardiff in December without flying?

Yes. La Chaux-de-Fonds reaches 6.7 °C cooler and is reachable by rail or ferry in 13h 48m (modelled), emitting 37.7 kg CO₂e return — though Rovaniemi is cooler still, if you fly.

How much carbon does a return trip from Cardiff to Rovaniemi produce?

581 kg CO₂e for one person, return, by air. That uses the UK Government's 2026 conversion factors, including radiative forcing for flights.

Carbon uses UK Government (DESNZ/DEFRA) 2026 conversion factors applied to great-circle distance, with radiative forcing included for flights. Rail journey times are modelled estimates, not timetabled services. Full method · download the data.