The Large Blue became extinct in 1970s in Britain and has subsequently been re-introduced to several sites.  Most of these sites are sensitive, many of these are kept secret, are private, and have no Public access.

But one site where the Large Blue can be easily seen during its brief flight period is the National Trust reintroduction site at Collard Hill in Somerset.  Its a great place to see Large Blue as it takes pressure of the other more sensitive sites.  It is managed for the Large Blue and has plenty of wild Thyme, Marjoram, and other food plants. Its a success story and the numbers are growing very well.  The numbers seem to be growing each year and it is estimated that at Collard hill there are between 1500 and 2000 Large Blue butterflies.

Although the Large Blue is Britans largest Blue butterfly, with a wingspan of 38 - 48mm it is quite small compared with some of whites, and browns.