Strikes are a regular occurrence in Europe, as employees withhold their labour to fight for better pay and conditions.
Walkouts are sometimes planned months ahead but others are announced last minute, showing that it always pays to check before you travel.
Luckily, we have gathered all of the strike information together below.
Read on to find out where and when are walkouts taking place.
If your flight or train is cancelled or delayed, you will be entitled to a new ticket or compensation. Read our guide for the full details.
UK: Heathrow Border Force worker strikes in April and May
Border Force workers at London's Heathrow Airport plan to walk out from 29 April to 2 May over plans to lay off staff.
This could cause major disruption for international flights. A smaller scale 'work to rule' strike between 3-18 May could cause further disruption.
Heathrow flights could also be grounded on 4-6 May as 50 refuelling workers stage a 72-hour strike over cuts to their benefits.
Gatwick Airport: Catering workers to strike on easyJet and TUI flights
Passengers on easyJet and TUI flights departing from London's Gatwick Airport will be left hungry as Dnata catering workers go on strike.
Around 100 workers, including HGV drivers and warehouse workers, will strike from 26-29 April, 3-6 May and 10-13 May. Strike action will intensify if the dispute over pay is not resolved, the Unite union has threatened.
Train strikes in April and May
While there is no national train strike planned in the UK, various localised action is planned for April.
London Underground workers will walk out on 26 April with last minute station closures possible, and disruption continuing into Saturday morning. An overtime ban from 29 April to 5 May could cause further station closures.
Members of train drivers' union ASLEF are also set to strike on 8 May, as well as taking part in an overtime ban from 6-11 May, which is likely to mean cancellations on some lines.
Impacted services include Avanti West Coast, Chiltern Railways, CrossCountry, East Midlands Railway, Great Western Railway and West Midlands Trains.
Belgium: Strikes threatened at Charleroi Airport
Brussels' Charleroi Airport has issued a strike warning that lasts until the end of April.
Catering staff and baggage handlers are expected to walk out at the start of May if their concerns over working conditions are not addressed.
France: Air traffic controllers cancel strike
SNCTA, the largest union representing air traffic controllers in France, has dropped plans for a 24-hour strike on Thursday.
However, the deal came too late to roll back cancellations ordered by France's DGAC civil aviation authority, meaning many flights will still be grounded on 25 April.
It is thought that it could affect up to 75 per cent of flights at Paris Orly and other major airports.
Over 300 Ryanair flights across Europe could also remain cancelled on Thursday due to the strike threat, with members of the smaller UNSA-INCA and Usac-Cgt unions still likely to go ahead with the walkout.
Could strikes hit Paris Olympics?
CGT-RATP union members announced a seven-month strike notice from 5 February to 9 September that could hit the Ile-de-France bus and metro network - including during this summer's Olympic Games.
However, the French Senate adopted a bill on 9 April to allow the state to ban transport strikes for set periods each year to avoid disruption during major events like Paris 2024. It also calls for more advance warning of strikes and increased minimum service obligations.
The bill faces opposition and must be adopted by the French National Assembly before it becomes law.
Workers at the state-owned public transport company say they are walking out over pay.
Germany: Threat of various strikes ends
On 25 March, Deutsche Bahn reached an agreement with Germany’s GDL train drivers' union, bringing an end to five months of negotiations and strikes.
The deal means that GDL will abstain from strikes until at least February 2026.
German union Verdi has also called off strikes at various German airports after reaching a pay deal.
If you know of a big strike happening in your country that we have missed, we'd love to hear from you via Twitter.