The other day I went to the Palace Museum in Taipei. The new exhibition displayed and ink rubbing from the stele for the Duke Zheng Wengong 熒陽鄭文公之碑墨拓本. A stele is a stone slab erected as a monument. This stele is dated Northern Wei dynasty (386-535), but the rubbing is newer. Nevertheless steles before the Tang dynasty (618–907) are rare and give us a glimpse of Chinese characters before their formalisation during Tang.
What I found fascinating about the rubbing is how some stroke-parts (usually written without lifting the brush) appear to be written with a new stroke. I am not suggesting the author of the original inscription did, but still…
There is a full resolution image of one of these rubbings here.