Why is my UI so big??

I've seen videos of Civ 5 and wonder why their game looks so much nicer than mine and saw that its cause of the UI (I like looking at the landscape and my border ^^) but my icons for resources, units, cities, etc are much bigger so it takes up most of the screen. How do i fix this?

P.S I assume its resolution, but i hope it isnt (My in-game resolution can't go higher then 1600 x 900)

It is resolution. But there's something you can still do about it. See the settings highlighted here:I have mine unchecked because I found the city banners unreadable on the "small" version. But if you have those checked, it will shrink some elements of the UI for you.

It looks from the pictures posted that the OP is already using the small version of the UI (which is still much too big, IMHO). [I say this because I play in 1920*1080, and the pictures seem identical]

I think a lot of LPs and YouTube videos use the Enhanced User Interface mod, which may but what the OP is referencing.

Unfortunately, the CIV V UI is clunky (kind of like the AI) -- you just have to get used to it.

It is already on Small scale interface :'( Well can't say i never tried, Thanks for the help

At first this got me really confused, thinking it was about oversized unique improvements.