How can you get the first digit in an int (C#)?

In C#, what's the best way to get the 1st digit in an int?

The method I came up with is to:

• turn the int into a string,
• get the 1st char of the string, and
• turn the char into an int.

Like:

int start = Convert.ToInt32(curr.ToString().Substring(0, 1));

While this does the job, it feels like there is probably a good, simple, math-based solution to such a problem. String manipulation feels clunky.

Edit:
Irrespective of speed differences, mystring[0] instead of Substring() is still just string manipulation