A tennis court was once located on the southern periphery of Alnwick garden. It was laid here by at least 1945 as it is shown on aerial photography nestled within the gardens, and is again illustrated on Ordnance Survey maps from c1950s. On this map, it depicts the rectangular court with a small clubhouse, implying a club used the site or was privately used by the Duke of Northumberland and/or his estate. This was just before and just after it closed as a working garden, as it reopened for tourism in the late 1990s.