Can anyone recommend a very basic calendar program?

I really need to start organising things and a calendar on my PC where I could set up events would really help. No other fluff, quite literally just a program that shows me the current month and handles events, perhaps with like a notification function or something along these lines.

Given how simple this would be I'd code one myself, but I haven't got the time to do so at the moment, so I just wanted to ask if anyone's able to recommend something similar to that.