There's an xkcd what if that made me realize how deep/shallow the oceans are in various places. https://what-if.xkcd.com/53/ https://what-if.xkcd.com/53/ Bonus

There's an xkcd what if that made me realize how deep/shallow the oceans are in various places. https://what-if.xkcd.com/53/ https://what-if.xkcd.com/53/ Bonus - what happens to Mars if you dump all the water there: https://what-if.xkcd.com/54/ https://what-if.xkcd.com/54/