This rather lovely iris, which I think is probably an old Iris spuria hybrid (not the typical I.spuria which is blue), is growing on the site of the old colliery at Dawdon on the Durham coast. There's a second plant growing on the cliffs nearby.
It's tempting to speculate that these plants are survivors from the gardens of the old terraced colliery houses, which were demolished along with the colliery many years ago. The site is now open limestone grassland, covered with wild flowers.
To see some pictures of another unusual garden escape iris, Iris sibirica, on sand dunes on the Northumberland coast, click here