I am searching for an extension

You can do that with main JEvents component. Please check this document for further reference:

http://www.jevents.net/jevents-15-topme ... csv-format

thank you for your reply
I know this article, I understand how to build the csv file, but I do not understand how to import. This seems to be done with a url? but in what form?

Hello,

You can do it from file or url.

Go to:

Joomla! Admin
Components
JEvents
Calendars

And create new, then select from file or url.

Thanks
Tony

Thank you for the good information..Thanks for sharing...