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The London Eye is a 443 ft (135m) high Ferris wheel with 32 air-conditioned observation capsules, each accommodating up to 25 people (or 170 foreign tourists). Tickets typically cost around £30 per person, though you can hire low-tack shoe stickers (£1.99 for four) to attach yourself to the exterior of the capsule.
Although it is undoubtedly a landmark work of engineering excellence, it does have one inherent and fundamental flaw. It gives you uninterrupted views of London.