Extremly flexible event manager

This plugin is extremly flexible in the configuration. You choose if you want to use custom WordPress templates, or adapt right in the admin area those that come with their built in template engine. You have robust support of recurring and multi day events. There are even various options to have registration right on the site. You have the possibility to enable registration on the front end and if needed you can extend almost everything with custom programming, and there is a good documentation on how to do that. Quite satisfied to have chosen this option, and am using it already for years!