This is a lily rather than a crocus. Meadow saffron has goblet-shaped, bright pinkish-purple flowers that grow on top of slender pale stems that are attached to an underground corm.
The meadow saffron flowers in the autumn, so the plant is also known as autumn crocus. The summer leaves are large and strap shaped, but die back before the flowers appear.
The leaves are poisonous to farm stock, so in some areas of the countryside it is still regularly removed from fields about to be grazed.

It is a lovely plant to grow to brighten woody places in autumn, just as other plants are beginning to fade. It provides late nectar and pollen for bees and other pollinators.