Hello.
Posting photos/videos/reviews on Google maps is similar to participation in world’s game! I check my “new views” each week (thanks to Google’s notifications) for several years already.
I have started posting photos approximately in 2010 during the honey moon and I can’t stop do it. Place and topic doesn’t matter for me. 
I don’t have any preferable things to share. I could start from famous Niagara waterfall, continue with highest CN tower in Toronto,
add Photo of small church somewhere in not know village in Ukraine and finish with a photo of sandwich in not known cafe.
I used to always wondering, how Google knows all that places and now I know the answer - all local guides help Google share useful information to humanity.
It is a great honor to be a part of such huge community and share information with other people.