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Brussels · September · relief from the heat

Coolest places to go from Brussels in September

The coolest place you can reach from Brussels in September within 15 hours is Reykjavik, 9.6 °C cooler, costing 535 kg CO₂e return. The lowest-carbon option is Villingen-Schwenningen at 12.7 kg — 42× less carbon, for 7.2 degrees less relief from the heat.

The 10 coolest places within 15 hours of Brussels

Ranked on relief from the heat in September 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. Reykjavik, Iceland9.6 °C cooler · 6.3 h sun a dayair 6h 18m · 535 kg CO₂e return
  2. Tromsø, Norway7.4 °C cooler · 4.9 h sun a dayair 6h 30m · 560 kg CO₂e return
  3. Östersund, Sweden6.4 °C cooler · 7.7 h sun a dayair 5h 30m · 378 kg CO₂e return
  4. Bodø, Norway6.2 °C cooler · 5.2 h sun a dayair 6h · 480 kg CO₂e return
  5. Rovaniemi, Finland5.9 °C cooler · 6.0 h sun a dayair 6h 18m · 531 kg CO₂e return
  6. Trondheim, Norway5.3 °C cooler · 7.0 h sun a dayair 5h 24m · 363 kg CO₂e return
  7. Sundsvall, Sweden4.8 °C cooler · 8.4 h sun a dayair 5h 30m · 378 kg CO₂e return
  8. Luleå, Sweden4.8 °C cooler · 7.7 h sun a dayair 6h 6m · 485 kg CO₂e return
  9. Dundee, United Kingdom4.7 °C cooler · 7.7 h sun a dayrail 11h 18m · 56.3 kg CO₂e return
  10. Glasgow, United Kingdom4.1 °C cooler · 7.2 h sun a dayrail 10h · 54.1 kg CO₂e return

Without flying

The coolest places the train reaches within 15 hours. Dundee is 4.7 °C cooler for 56.3 kg — about 9× less carbon than flying to Reykjavik.

  1. Dundee, United Kingdom4.7 °C cooler · 7.7 h sun a dayrail 11h 18m · 56.3 kg CO₂e return
  2. Inverness, United Kingdom4.6 °C cooler · 7.3 h sun a dayrail 13h 6m · 66.9 kg CO₂e return
  3. Aberdeen, United Kingdom4.3 °C cooler · 8.4 h sun a dayrail 12h 30m · 60.9 kg CO₂e return
  4. Glasgow, United Kingdom4.1 °C cooler · 7.2 h sun a dayrail 10h · 54.1 kg CO₂e return
  5. La Chaux-de-Fonds, Switzerland3.0 °C cooler · 9.2 h sun a dayrail 8h 30m · 13.4 kg CO₂e return
  6. Kristiansand, Norway2.8 °C cooler · 8.2 h sun a dayrail 14h 12m · 24.9 kg CO₂e return

Rail times are modelled; air times include getting to and through the airport.

The low-carbon trade-off

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

Villingen-SchwenningenReykjavik
Where they are. Solid lines are rail or ferry, dashed are flights, from Brussels. Pick one to compare.
Carbon against relief from the heat, September, departing Brussels. Journeys of up to 15 hours each way.7 destinations. Lowest carbon Villingen-Schwenningen at 12.7 kilograms and 2.4 °C cooler; best for relief from the heat Reykjavik at 535 kilograms and 9.6 °C cooler. Villingen-Schwenningen · 12.7 kgStirling · 55.3 kgKristiansund · 347 kgReykjavik · 535 kg

By rail or ferry By air

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

What the 15-hour limit costs: at this budget Östersund can only be reached by air — 378 kg CO₂e, in 5h 30m. Allow up to 24 hours and the train does the same journey for 44.3 kg in 23h 42m — 9× less carbon for 18h 12m more travelling.

September from Brussels — 7 destinations on the frontier, 4 without flying.
DestinationHowCO₂e returnTempSun/dayRain/dayJourney
Villingen-Schwenningen, GermanyRail12.7 kg14.7 °C9.3 h3.0 mm8h 12m
La Chaux-de-Fonds, SwitzerlandRail13.4 kg14.1 °C9.2 h3.5 mm8h 30m
Buxton, United KingdomRail27.9 kg12.8 °C7.1 h3.9 mm8h 18m
Stirling, United KingdomRail55.3 kg12.3 °C7.2 h3.3 mm11h 6m
Kristiansund, NorwayAir347 kg11.6 °C7.1 h6.5 mm5h 18m
Östersund, SwedenAir378 kg10.7 °C7.7 h2.6 mm5h 30m
Reykjavik, IcelandAir535 kg7.5 °C6.3 h3.5 mm6h 18m

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 Stirling (55.3 kg, 4.8 °C cooler) to Kristiansund (347 kg, 5.5 °C cooler) buys 0.7 °C more relief from the heat for an extra 291 kg — 416 kg of CO₂e per degree. That single step is the most expensive relief from the heat on the whole curve.

The pick of them

Villingen-SchwenningenGermany12.7 kg CO₂e return14.7 °C · 9.3 h sun · 8h 12m by railmild and brightStirling, United KingdomStirlingUnited Kingdom55.3 kg CO₂e return12.3 °C · 7.2 h sun · 11h 6m by railmild and brightReykjavik, IcelandReykjavikIceland535 kg CO₂e return7.5 °C · 6.3 h sun · 6h 18m by aircool

The same month, asked differently

September 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 Reykjavik

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

Search places to stay in Reykjavik →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 Brussels

September from elsewhere

Photo credits

Questions

Where is the coolest place to go from Brussels in September?

Reykjavik, Iceland, at 9.6 °C cooler. Reaching it emits 535 kg CO₂e return, travelling 6h 18m each way by air (modelled).

Can I get somewhere cool from Brussels in September without flying?

Yes. Stirling reaches 4.8 °C cooler and is reachable by rail or ferry in 11h 6m (modelled), emitting 55.3 kg CO₂e return — though Reykjavik is cooler still, if you fly.

How much carbon does a return trip from Brussels to Reykjavik produce?

535 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.