A stone vessel said to be around 2,000 years old, once used to gauge the rise of the Nile, sits in this walled garden behind Warwick’s medieval Lord Leycester Hospital. The space has been gardened since at least the 16th century and was replanted in its current form last century, with a 12th-century Norman arch and a big mature magnolia among the beds. Paid entry, usually alongside a visit to the hospital itself.