You can subscribe to one or more of these calendars in iCal format for use with iPads.  Use the following links for each specific calendar.  

To subscribe to these calendars with your iPad or iPhone, first tap and HOLD the link below until the "Copy" option appears.  Choose "Copy," then go to Settings > Calendar > Add Account > Other > Add Subscribed Calendar. Tap the "Server" field once, then tap "Paste."  Tap "Next," then "Save."  The events from the subscribed calendar will begin to populate.