If you're heading to London, one of the best bits of travel kit you can get is an Oyster card. Similar to Hong Kong's Octopus card, the Oyster is a prepaid tap-and-go smartcard used on public transport throughout London.
It covers the extensive London Underground or Tube network, the London Overground and most suburban stops on the National Rail lines (to be specific, stations in Zones 1 through 9 – download the London Rail & Tube Map [350KB PDF] to get your head around the travel zones.
You're also covered for buses and the Docklands Light Railway (DLR), which goes out to the financial centre in Canary Wharf and to London City Airport.
The Oyster is also accepted in some cafés and newsagents where you can make small-value purchases with a quick swipe of the card instead of digging around for change.
If you need some more reasons to pocket an Oyster, consider that it can be more than half the price of paying for your Tube or bus fares in cash.
There's also a daily price cap, which for instance lets you zip around Zone 1 in the heart of London and pay no more than £8.40 no matter how often you travel.
But in true British fashion, the rules and regulations are a bit complicated – so here's our guide to getting and using an Oyster card in London.
How to buy an Oyster card in London
Oyster cards are for sale at all Tube stations, including Heathrow Airport's Tube stations – although there's quite often a queue to buy them at Heathrow.
Although you can't use Oyster cards on the Heathrow Express, if like most London-bound travellers you take that high-speed train from Heathrow to Paddington you can pick up your Oyster card when you arrive at Paddington Station.
The card itself carries a refundable £5 (A$8.60) deposit and can be loaded with up to £90 over the counter or using automated machines which take credit cards and cash.
Note that if you don't have a chip-and-PIN card which your Australian bank has confirmed will work in the UK, you may have to line up at the ticket office (unless you have enough cash to top up your card).
You can also buy an Oyster before you fly off for London – click here for a list of Australian Oyster agents. It can be more convenient to get this out of the way, as long as the prices aren't too much more than buying the card in London.
Once you're in London and on the move, you can check the balance of your Oyster card at Tube stations or by using one of the many iPhone and Android apps (just search the iTunes Store or Google Play for 'Oyster card' and you'll find free and paid apps on offer).
Using your Oyster card
The first bit's pretty simple: touch the card to the Oyster reader when you get on a train or bus. You can keep it in your wallet and just wave your wallet across the reader.
The trick is that when travelling by train (including light rail) you also need to touch the card when you exit the station at the end of your trip. That's when the Oyster system calculates your travel fare from start to finish and deducts it from your card.
Forgetting to 'touch out' is a classic rookie mistake, especially on the DLR in the Docklands financial district, where there are fewer platform gates.
Unfortunately, it's a mistake that'll see you charged an 'incomplete journey' fare of up to £8.30 (A$14.30) – which doesn't count towards Oyster's daily price cap, so you could be up for a double whammy at the end of the day.
If you're hopping around on London's iconic red buses you need only touch on when you jump on board – your Oyster card will be debited immediately at £1.40 per trip (compared to £2.40 if you pay cash) and capped at £4.40 for a whole day's tripping around.
In fact, despite their often confusing routes, buses are excellent way to see London and can be faster than Tubes on some journeys.
How do I get my money back off my Oyster card?
At the end of your trip, you'll probably have some money left on your Oyster. If you're planning a return journey to London, keep hold of it for next time!
If not, simply hand it back at a ticket office (probably the one at Heathrow) and your money will be refunded in cash.
Just be sure to leave some time for this process, as the Heathrow Tube stations are notorious for delays at seemingly random times of day.
Additional material by John Walton.
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