Powerful jQuery Event Calendar: wdCalendar
wdCalendar is a jQuery plugin that enables us to create an event calendar that functions similar to the popular Google Calendar.
With a drag'n drop interface and feature-rich API, it is possible to create, update or delete events easily.
It has custom views for day, week or month where you can easily go to a selected date (also with the help of provided JS methods).
Usually, multi-day events are complicated, however, wdCalendar handles them well.
P.S. The resource website also shares other useful plugins for a tree menu display, date-picker and more.