Boston, not a city I have seen much of. I have been there twice for work. The first time was a quick in and out, with tons of meetings. I was back recently for three and half days, and it rained non-stop for the first 24 hours, then it fogged in. It cleared as I was heading the airport to return home. It is an old and historic city, someday I will see it.
This last trip my hotel room allegedly looked out at the Charles River and a couple of massive office towers. I have to assume the river and building were there, between the pissing rain and the fog, the view was just a glimmer and legend.
I did see the inside of the "Big Dig." Boston buried all of cross town expressways in tunnels underground. It cost a mountain of money, took years to complete, and I understand made quite a mess of traffic. In the end they have created a massive underground traffic jam, to go complement the traffic jam on the surface. I took a taxi to the airport, a man with a walker passed us - moving faster on the sidewalk than traffic was moving, I watched him disappear over the horizon as the taxi meter ticked on.
For the engineering geeks, the most of the tunnels were created with "cut and cover", you dig a trench, build walls on the sides, build a roof over it, put a road in it and put the city back over the top of it. This is why the streets vibrate in places. I am not sure if the underwater sections were done with TBMs, or if it was built with surface tubes, essentially a pipe laid on the bottom of the water and then the water pumped out. The Metro tunnel under the Potomac was built that way (few people know that and it freaks some people out to hear that they are essentially traveling through a garden hose on the river bottom.) Pray that those pumps keep working.
Someday I will go back, I wanted to see Harvard Square, but I didn't have hip boots or x-ray vision.
What city have you been to and not seen?