I wasn't underwhelmed per se (the thing is mind-bogglingly huge).
I just was on one of those "middle aged friend couples go to Europe" trips. Most of my world travel has been solo, and I like to briskly walk around for miles and miles and just see how the city is laid out. "Slowly shambling around cathedrals" was much of the trip, so I was frequently irritated on that trip, particularly so at Sagrada Familia as it must have been the 12th cathedral we shambled around in 3 days.
> I like to briskly walk around for miles and miles and just see how the city is laid out
We would travel well together. My wife and I usually do this. We regularly clock up 20-25km a day of just walking around a city, often for 3 or 4 days in a row. We will happily walk from the centre out the the suburbs. From the far west to the far east of a city. We'll retrace our steps and then take a right that looks vaguely interesting. We only start to use the transit system to get further out or when we are short on time.
I just was on one of those "middle aged friend couples go to Europe" trips. Most of my world travel has been solo, and I like to briskly walk around for miles and miles and just see how the city is laid out. "Slowly shambling around cathedrals" was much of the trip, so I was frequently irritated on that trip, particularly so at Sagrada Familia as it must have been the 12th cathedral we shambled around in 3 days.