East
Behind that tree the sun is rising in the east. The sun always rises in the east, so if you head that way, past the tree, you'll be going east too.
Picture the sun behind the tree, don't picture the sun alone, you'll burn your eyes. It's slowly coming up behind it. Now think: where does the sun rise? In the east!
とう
ひがし
None
You walk east for a few hours until you finally come to a city. It's とうきょう. Oh! とうきょう is in the east. I get it now!
When you think about East Japan think about とうきょう. And if you're bad at geography, just look at a map for a while. Or, stand outside in the morning, watch the sun rise behind the trees, and point that way. That's east, it's where とうきょう is!