My location is an incredibly fashionable place to be.  Not to brag... but I have been a trendy retreat for aristocrats and wealthy people since the Roman times.

The country I run through has nicknamed me Lario. 

I am of glacial origin, and I'm shaped very much like the character "Y".  I am the third largest lake in my country and one of the deepest throughout my entire continent.

To this day, I remain a very popular tourist attraction with many artistic and cultural gems.  Without name-dropping, I can tell you that many celebrities have homes on my shores... and that one American leading man in particular speaks often about how much he loves coming to his home on my shores.

Where am I?