Source?
It's pretty stupid that multiple posters have had to ask for sources.
I'm sorry I didn't realize that this was such an important point of contention that I needed to find a source. But here's what I have.
My initial source for UVA was the dean of admissions when I interviewed (2014-2015 cycle) who told us that half of all students at UVA score 240 or above on Step 1. That suggests that the median step 1 score at UVA was at least 240. However, this was found to be incorrect because UVA publishes their finalized data on their website (see above). Thus the information given to me was incorrect. My apologies for thinking that information that I got from what initially appeared to be a reputable source was incorrect.
At my Duke interview day (same cycle), I was told something similar, though given that the information given to me at my UVA interview was incorrect, it is possible the same is true for Duke. It's possible that current Duke students have access to their school's median step 1 scores and can provide more precise information.
For Columbia, we were given a powerpoint presentation about recent scores on Step 1 and Step 2. For Step 1, the powerpoint said that median score ranged from 239 to 241 depending on the year. I double checked this on the powerpoint just now. I am not permitted to share these resources, so you can either take my word for it or not (or ask another Columbia student and have them verify).
If you want another one with source, Baylor's mean has been >240 for the past several years (
https://www.bcm.edu/education/schools/medical-school/prospective-students/success-indicators), though because it's the mean, it could be affected by skew.
There really aren't a lot of reliable sources out there for schools outside of information given to current students by their administration. Some schools publish their medians, but most don't. USNWR has "medians" behind their paywall, but their accuracy is questionable.