The Earth's continental crust varies in thickness, but it's generally considered to be between 35 and 70 kilometers (22 and 43 miles) thick.

Here's a breakdown:

* Average: Around 35 kilometers (22 miles)

* Mountain Ranges: Can reach up to 70 kilometers (43 miles)

* Plains and Plateaus: Can be as thin as 25 kilometers (16 miles)

It's important to note that this is an average range, and the actual thickness can vary significantly depending on the location and geological history of the region.