Re: Oyster Card: They have a capping system, meaning that you only pay a certain maximum per day and if you're over that limit - limits vary depending on the zones you visit and whether you're travelling on or off peak -, you won't get charged for the rest of your rides that day. If you're in London for 2 days, I suggest putting £15 on it, for 4 days I'd do £30. For longer stays, it's also worth looking into a travel card for one week, which you can load onto your Oyster Card :)

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