On the Borders

From an old Q&A by an Atwater Village real estate agent:

One thing interesting about Atwater is that in a city of amorphous neighborhoods, Atwater has very defined and well-recognized borders.

To the west it's the LA River and I-5...

To the east it's the railroad tracks...

To the south it's Fletcher Drive...

The northern border isn't quite so clear. Easily put, it's the Glendale city limits, but there's a spit of City of Los Angeles land that protrudes deep into what you would think is Glendale.

So on the north, should we just go with the Colorado Blvd. ramp to I-5? There isn't much above that.