A group of travellers have pitched up off Stafferton Way in Maidenhead at the site used for the park and ride service during the Olympics.
Between 15-20 caravans are based there.
Travellers at the site said they had been there since Friday and have been told they must leave by today or bailiffs will be sent in.
They refused to give any further comment.
UPDATE: 1.20pm: The group vacated the Thames Water-owned land this morning.
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