Map of US 6 in Provincetown MA
The USGS topo shown below was made in 1972. I don't know the date of the aerial photo, but I'd say roughly 2007:
The topo map was made back when US 6 and MA hwy. 6A ended at a large, oblong, complicated rotary. The aerial photo shows how that whole area has been reconfigured into a much more simple junction (I'm told the change took place in 1982). It's interesting how some of the scars from the old roadways are still visible on the photo. You can also see that the actual geographical location of the terminus of US 6 hasn't changed by more than a few yards, but the geometry of the endpoint has changed tremendously. Now you can drive right past the endpoint of US 6, and suddenly find yourself on MA 6A, perhaps without even realizing that you've just reached the end of one of the longest highways in the US. More info and photos can be found on my main Provincetown page.