London is the capital and largest city of England and the United Kingdom. The city stands on the River Thames in the south-east of England, at the head of its 50-mile (80 km) estuary leading to the North Sea. The City of London, London's ancient core and financial centre − an area of just 1.12 square miles (2.9 km2) and colloquially known as the Square Mile − retains boundaries that closely follow its medieval limits.

Tenerife is the largest and most-populated island of the eight Canary Islands. It is also the most-populated island of Spain, with a land area of 2,034.38 square kilometres (785.48 sq mi). Tenerife is one of the most important tourist destinations in Spain, hosting one of the world's largest carnivals , the Carnival of Santa Cruz de Tenerife. Tenerife is served by two airports, Tenerife North Airport (site of the Tenerife disaster, which killed 583 people) and Tenerife South Airport.