The earliest memory that I can remember is when I was riding in a Taxi in London late at night after getting out of the airport. It was raining hard and I just looked out at the strangely designed houses and streetlamps. I guess the extraordinary circumstance is the uniqueness of it all and the wonder that accompanies new discoveries. My personality has changed significantly since then and I no longer look at things with the same wonder that I did when I was younger. I guess I was about 6-7 years old at the time.
I love that your earliest memory was of something as pleasant as visiting London and being filled with wonder. Maybe you really enjoy exploring new things now? That could be a personality similarity?