The contract includes the motorway service station on the M40 at Beaconsfield and a new site between junction nine and junction 10 on the M25 near Cobham, set to open in time for the London 2012 Olympic Games.
The nine Extra service stations include retailers such as Shell, Marks & Spencer Simply Food, WH Smiths, KFC, Starbucks and McDonald's.
The deal rounds out Admedia's national service station portfolio. In addition to its well known washroom media portfolio, Admedia sells advertising on up to 1,300 six-sheet poster panels in 130 motorway service areas across the country.
Adam Mills, managing director at Admedia, said: "Every one of Extra's Motorway Service venues provides a real attraction for motorway drivers, offering a combination of modern, state of the art destinations with quality retailers.
"Our completed motorway advertising package offers massive footfalls and access to a range of different audiences every day – a really attractive proposition to clients, not to mention a unique opportunity around the Olympics."
In June this year Admedia launched Admedia Connections, a new interactive offering to help advertisers who want to combine mobile technology with their static poster campaigns across 900 pubs and bars.
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