Europe's biggest dedicated online fashion retailer Zalando, which is growing at breakneck speed, is planning to develop a new campus headquarters in a trendy part of Berlin to house 5,000 employees.

Zalando said the ground-breaking ceremony would take place in the second quarter of 2016, and the opening was targeted for 2018.

The biggest building in the new campus, located between the Ostbahnhof and Warschauerstrasse stations near the Spree river, will be a seven-storey glass-encased office built by Muenchner Grund Immobilien Bautraeger GmbH and rented by Zalando.

Zalando declined to say how much it was investing in the campus, which will also incorporate buildings the company is already occupying.

Founded in Berlin in 2008, Zalando now serves customers in 15 European markets with over 1,500 brands. It is quickly becoming one of the biggest employers in the German capital, long plagued by high unemployment.

In March, Zalando said it was going on a hiring spree to increase its staff to about 10,000 by the end of 2015 from around 8,000 now, hiring particularly in the tech and logistics field, but also in fashion and operations.

Last week, it said it would reach close to 3 billion euros ($3.20 billion) in revenue for the full year, reiterating a target for growth of 33 to 35 percent.

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