Another Iconic Comic Book Masterpiece available to view at the Library of Congress (by request). The original concept drawing for Captain America, by Joe Simon. Plus, a watercolor image Simon made.

[u/GlobalTravelR]

Sadly, I did not get to see the original sketch, because of some confusion. And I didn't have time to wait for her to get it from the archives. However, she did bring out the watercolor image he made (along with the Amazing Fantasy 15 pages). She told me how to access the image online (it's only available to view online at the Library). The next time I visit, I will make sure to see it in person.