Greyhound will give Christmas passengers a discount of 25 per cent if they plan to visit the heritage area.
Customers booking online with Greyhound should use the promotional code 'dockyard' to get the reduction, or bring their Historic Dockyard ticket with them if they are travelling away from the dockyard.
A dockyard ticket provides walk on customers with a ticket reduced from £10 to £7.50.
Alex Warner, managing director of Greyhound UK, said: 'We are delighted to form this partnership with the Historic Dockyard.
'I hope that between us we can encourage more people to visit Portsmouth during the Christmas holidays.'
Robert Bruce, managing director of the historic dockyard said: 'Aligning ourselves with Greyhound tightens our relationship with London visitors, which can only add to the numbers visiting the Historic Dockyard.'
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