Yes, you do need to have a visa stamp for going to the UK. In order to travel to Great Britain, you have to have a Visa to get there. Because without the visa logo on your passport, they won't let you in. Expecally if you're going to be on the International Airports. Once you're at the British Airways, and you pass the TSA security service, show them your visa at the gate then they'll let you in, if you don't have it on you're passport book even if you've forgotten about it by mistake, they would not let you enter the plane. Only the British Airways will allow British visas from travelers to get it done. Be responsible about it, learn about it, and have it with you before to travel to United Kingdom of Great Britain. This will help you on you're journey to get the adventure what you wanted. Good Luck on you're future travel.
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