[Always Right]

The last ice age started to end about 20,000 years ago, but it started over 100,000. My number was an order of magnitude off though, lol.

[Doe Eyes]

The last ice age started to end about 20,000 years ago, but it started over 100,000.

I did a little looking, and if ice age is defined as the period when there are major areas of ice present on earth, versus periods of no ice, your original number may be correct.