You will want to start with the National Rail System http://www.ns.nl

Leiden is 20 minutes away from Delft.

Groningen is 1:45 hour to the North.

Lots of small bus and trolly car connectors

Read - Research - Study - Get a MAP!!! Check the university callendars.

Sincerely,
Gargoyle

You cannot possibly be as pathetically helpless as you are trying to appear.