Amazon Web Services just opened a new set of cloud data centers in London, continuing its expansion. The London facility represents what Amazon calls another cloud “region” in Europe which joins the company’s long-standing data center farm outside Dublin, and another set of facilities in Frankfurt.
The news comes a week after Amazon opened another public cloud region operating out of Montreal, bolstering its North American presence.
Many companies are turning to public cloud services offered by the likes of AWS or Microsoft (MSFT) to augment or even replace their own data centers. Cloud service providers aggregate huge masses of connected servers and storage gear and rent that computing capacity to customers, typically on a pay-as-you-go basis.
Amazon (AMZN), Microsoft, Google (GOOG), and IBM (IBM) are all building out more cloud data centers worldwide for a few key reasons.
Get Data Sheet, Fortune’s technology newsletter.
First, in general, the closer a data center is to the customers using its services, the faster the performance. Distance adds latency or delay to operations. Second, some countries, including Germany and Switzerland, have strict data sovereignty rules governing where citizens’ data can be stored. That requires cloud providers to guarantee that this information stays in the country of origin. That’s why Amazon, Microsoft, and Google all rushed to add German data center facilities, in particular.
For more on cloud services, watch:
The United Kingdom has long been a key focal point for American cloud giants, and the region is probably even more key given the Brexit vote. Last month, IBM said it planned to triple its cloud data center presence in the U.K.
Microsoft announced plans for new London-based cloud facilities in September. They are expected to come online in the first half of 2017.