Utilize the input text as a context reference, choose the right relationship between apartment and London from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

It became their central London base: a cool contemporary apartment worthy of Manhattan (Hamburg: 32U.HM - news ) , but with views over Hyde Park, not Central Park.

Answer: location_of_formation