A couple of us are planning to visit the 9/11 Memorial in New York next month; it would be our first time visiting the Memorial. I want to be careful to not treat the event as some adventurous visit and to keep in mind that people are going there for a day of mourning and remembrance. This might be easier said than done, since there is also a 9/11 museum there that we plan to visit too.

And another thing that makes matters a bit more complicated is that 9/11 occurred almost 17 years ago now. For example, we could still say things like

I'm sorry for the loss of your son

but don't know if is that unnecessary or even discouraged at this point in time, in the year 2018. We want to be cautious of what we are saying, in order to show respect to the families and not inadvertently offend them.

How can we interact with the families that lost loved ones on 9/11 without offending?

I have never been to a place of mourning before - not a funeral, nothing - so I'm very inexperienced in such environments.