Why is the District of Columbia not a square?

Wasn’t the original plan for Washington DC to be a perfect square? What happened? Did Virginia reneg on the idea? Or was land sold back to VA at some point?

We had a pretty thorough discussion on this, just over a year ago:
If Washington’s a “district” where’s the rest of Columbia?

Originally, the district was a square tipped on one point. The rest of the details you can find in that thread.

In short; it was a square. However, the Federal Government gave Virginia it’s portion back sometime in the 1800s.

Zev Steinhardt

The Virginia portion mostly became Arlington County.

From the Arlington County, Virginia, history page: