This is a block in the British sense or senses, as given in the Concise Oxford Dictionary:
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2) chiefly Brit. a large single building subdivided into separate flats or offices. > a group of buildings bounded by four streets.

> chiefly N. Amer. the length of one side of such a block: he lives a few blocks away.
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'The dominant office block in a series of historic buildings interspersed with more recent ones ...'

- or whatever suits uour context.