The blue lights on the sea coast are the glowing firefly squid of Toyama, Japan. Each tentacle has an organ called a photophore, which produces light. When flashed, these lights attract small fish, on which the squid can then feed.
This is a bridge in Paris. You hang locks on it with the name of you & your boyfriend/girlfriend/bestfriend then throw the key into the river. So even though the friend/relationship may end, you can’t remove the lock. It stays there forever, as relevance to someone once a part of your life. -- Totally just added this to my bucket list!