This is the definitive guide to the 50 ages (and six heights) of a traveller.
Minus 12 weeks: The Civil Aviation Authority says: “Most airlines require a certificate after 28 weeks, confirming that the pregnancy is progressing normally, that there are no complications and the expected date of delivery.”
Minus eight weeks: British Airways does not carry women who are pregnant with more than one baby after 32 weeks.
Minus four weeks: BA will not let women with single pregnancies fly after 36 weeks.
Nought: You can travel free on public transport across the UK.
Eight days: Ryanair will let you fly on domestic routes, but your fare may be higher than your mother: the flat infant fare is £25.
You will not be allowed to fly outside the UK with Ryanair because you will not have a passport. However, you can reach Ireland on British Airways, which also has a minimum age of eight days for passengers and does not require a passport for travel within the Common Travel Area – including Ireland, the Isle of Man and the Channel Islands.
Two weeks: EasyJet will let you fly.
Three weeks: Assuming your parents applied for a passport on the day you were born, you can expect it to be delivered by now. Eurostar will take you through the Channel Tunnel from London St Pancras to Amsterdam, Brussels or Paris at any age.
Four months: Neilson will welcome you into its Starfish Creche, with a promise: “We have one nanny for every two babies. Experts in their field, they can recite any Disney song in a flash.” The weekly cost, on top of the price of the holiday, is £390.
The activity operator has eight separate age bands for children’s activities.
Six months: Crystal Ski’s Pepi Penguin Nursery is all yours, until you are four; prices start from £475 for six days.
Many cruise lines will allow you aboard, though for some longer voyages (typically those with three or more consecutive days at sea) the minimum age is one year.
Six months and one day: P&O Cruises will allow you on board most voyages.
Two years: On many scheduled flights you must pay the full fare (less Air Passenger Duty).
And it’s time to start paying the child fare on some trains. The railways of the Canada, Colombia and Namibia will charge you half the adult fare. On “weekday Acela trains” run by Amtrak in the US, it’s the full fare for you.
Three: Time to pay half fare on Taiwanese trains, and on Inca Rail links to Machu Picchu in Peru.
Full fare in Indonesia, but your parents are unlikely to be bankrupted as a result: the 100-mile trip from Jakarta to Bandung clocks in at a reasonable 63,000 Indonesian rupiah (£3), through the handy English-language website en.tiket.com.
What you pay on some other railways depends on how fast you grow.
90cm: You now need to pay half fare on trains in the Philippines. But you can ride on the Peter Rabbit Hippity Hop ride in CBeebies Land at Alton Towers, in the company of an adult.
100cm: Half-fare on Thai and Chinese railways.
110cm: Ditto, in Chile. Back in Alton Towers, you can go on that Peter Rabbit Hippity Hop ride alone.
3ft 8in (112cm): Until this height, you travel free on New York’s subway and buses.
Four: You start paying child fares on Eurostar and on many trains in Australia and New Zealand.
120cm: Time, or rather height, to pay full whack on trains in the Philippines.
Five: Most British and European rail and bus operators charge you half fare – though Transport for London allows anyone aged under 10 to travel free when accompanied by an adult.
Six: Time to pay half fare on Japan’s Bullet Trains. G Adventures’ family trips are now open to you.
Seven: Many of the most generous train operators are in southern Africa: Zambia, South Africa and Botswana Railway; you only start paying half fares now.
Across in Madagascar, though, adult fares now apply.
Eight: Minimum age for the Sydney Harbour Bridge climb – but you must also be at least 120cm tall.
PGL Children’s Camps are now open to you.
140cm: Minimum height for the five most exciting rides at Alton Towers, including Nemesis and Oblivion.
Nine: You are now eligible for some of Exodus Travels’ family activity holidays.
10: Flixbus will carry you on UK journeys on your own with signed permission from a parent.
11: To qualify for free buses and trams in London, and child-rate fares on the Tube, you must pay £15 for an 11-15 Zip Oyster photocard.
12: The age when many aspects of travel get more expensive. Train operators in most European nations insist you should pay full fare. And boys are now banned from ladies’ carriages on trains in Pakistan.
Most of those airlines that offer child fares make you pay full fare from age 12. No 1 Lounges now categorises you as an adult.
But there is some good news: Eurostar will let you travel unaccompanied between London, Brussels and Paris on trains departing before 5pm local time; for Amsterdam and Rotterdam, the minimum age is 16.
14: British Airways will allow you to travel on your own, though your parents/guardians must fill in a form. National Express will allow you to travel unaccompanied.
You can stay in a German youth hostel on your own, with your parents’ consent. And you can start driving with a learner’s permit in the US states of Alaska, Arkansas, Iowa, Kansas and North and South Dakota.
15: Intrepid will allow you on many of its trips, if accompanied by someone aged 18 or over.
15 years 9 months: you can apply for a provisional UK driving licence, but you can’t start driving a car until 17.
16: You are now expected to pay full fare on British trains, but you qualify for the 16-17 Saver which costs £30 per year and gets you half price on the railways.
Air Passenger Duty applies to all the flights you take from the UK, adding anything from £13 (short-haul economy) to £200 (ultra long haul in anything but economy).
On an easyJet or Ryanair flight, you can travel unaccompanied.
You can stay in a UK youth hostel without an adult.
Visiting London? You’ll now need the 16+ photocard to qualify for half-price travel, valid until age 18 (residents of the capital get extra benefits).
You qualify for Tui adults-only holidays.
And on a P&O cruise, you can be left unaccompanied on board at a port of call.
17: At last you’re an adult on Mozambique Railways.
18: British Airways, easyJet, Jet2, Ryanair and Virgin Atlantic will accept your application to work as cabin crew.
In New York State and Michigan, Hertz will hire you a car ($84 a day surcharge). And you can rent a car in Saskatchewan without any under-age fee.
19: Hertz will rent you a vehicle in Alabama and Nebraska. And you can legally drink in most Canadian provinces (in Alberta, Manitoba and Quebec the minimum drinking age is 18).
20: You can now legally order a drink in Paraguay.
21: Minimum age for renting a car with Hertz in the UK and many other locations, though a young driver surcharge is likely to apply.
23: Avis will rent you a car in the UK.
24: You are old enough to drive a bus in the UK.
25: Most of the car-rental surcharges vanish, and in the US Hertz will now rent you a Maserati or a Range Rover, but some rental car companies continue to impose restrictions on the kinds of car you can drive.
26: You no longer qualify for the 16-25 Railcard – though you can buy one on the eve of your 26th birthday, and it will be valid for a full year. The 26-30 Railcard takes effect, though its benefits are not as good.
Residents of the European Union must start paying to get into the Louvre (for non-EU residents, the age is 18).
27: You start paying a surcharge for youth hostels in Germany.
28: You are no longer a youth in the eyes of Interrail, which means you lose the discount of up to 25% on unlimited travel passes. Age benefits return when you are 60.
30: Hertz UK will now rent you a Ford Mustang, a Bentley GTC or a Lamborghini.
31: You no longer qualify for the Australia Working Holiday visa unless you are a British, Irish or Canadian citizen, in which case you can stretch it to 35.
36: You are now too old to stay in a dorm at the Hans Brinker hostels in Lisbon and Amsterdam.
Contiki, the youth travel organiser, will no longer accept you on one of its trips.
40: You are no longer welcome on G Adventures’ 18-to-Thirtysomethings tours.
50: You qualify for Saga holidays (though travelling companions can be as young as 40).
ScotRail invites you to join Club 50 (£15 annually) which is a kind of trainee version of a Senior Railcard. Scotland only, 20 per cent off advance and off-peak tickets. It also features flash sales of £17 return flat fares for any length of journey in Scotland
59 years 50 weeks: you can apply for, and start using instantly, a real Senior Railcard (£30 for a year). This will put you back on a par with those under 30, saving you one-third off rail travel in the UK. If you are feeling in good shape, buy the three-year version, price £70.
60: The National Trust confers a 25 per cent discount on annual subscriptions for the people it describes as its “bedrock”.
The charity says: “With your support, we can keep looking after nature, beauty and history for ever. We want you to be able to stay with us, so that's why this concession is there for you if you need it.
“The most important thing for us is to make sure you can afford to continue your membership and that is why we are happy to offer this concession.”
To qualify, though, you must have been paying the full annual subscription for at least three consecutive years.
Interrail will give you a 10 per cent discount off adult fares. No strings attached.
62: Isola 2000, a French ski resort 90 minutes north of Nice, offers a 16 per cent discount off a lift pass. Give it another decade and things get even better at high altitude (see 72).
65: Start watching for those insurance policies that reject or surcharge older travellers.
Commercial airline pilots must retire in many nations.
All public transport in the city of Prague is free, except for commuter rail services. For trams, trolleybuses and the Metro, there is no need to do anything beyond carrying your passport to prove your age if challenged.
66: Congratulations, you qualify for a bus pass in England (sexagenarians in Wales, Scotland and Greater London gain free transport benefits from aged 60).
70: Private pilots in the UK must start self-declaring to the Civil Aviation Authority that they meet the same health requirements as an ordinary driving licence – which mainly involve visual acuity.
72: Isola 2000 offers free lift passes for everyone this age or more. The same applies for everyone aged 4 or less.
75: Zipcar, which rents cars by the hour, insists that customers aged 75 or more have held a licence for at least two years and have no more than three penalty points.
Europcar will not rent you a car in Argentina or Lebanon. And the Sydney Harbour Bridge Climb demands a Certificate of Fitness signed by your GP.
But in the Trois Vallées of France, which claims to be “the world’s largest ski area,” 600km of runs are yours for free.
76: Europcar will no longer rent you a car from Plymouth, Exeter, Taunton or York.
80: Explore will “discuss the itinerary with you before booking you on the trip” and may ask “additional questions about your health and fitness”.
94: You currently qualify for a free UK passport if you were born before 3 September 1929. You can even use the Post Office check and send facility free of charge.
99: Many car rental firms will no longer hire you a vehicle (but Europcar will from most locations in the UK).
