Thanks to cheap storage and easy copying, our digital souls have the potential to be truly immortal. But do we really want everything we’ve done online – offhand comments, camera-phone snaps or embarrassing surfing habits – to be preserved for posterity? One school of thought, the “preservationists”, believes we owe it to our descendants.
Source: wiktionary
Last, but very much not least, are the portals of the Ffestiniog Railway's Moelwyn Tunnel. The tunnel's story itself is well told - it was part of the preservationists' deviation required to get around a reservoir that had flooded the earlier route. But the reason for its inclusion here is that it is probably the most recently constructed, properly architected tunnel portal in Britain.
Source: wiktionary