I’ve clicked the Photos link from the Google+ navigation menu. The page redirected to Google Photos and it displayed a new message:
“Welcome to Google Photos, the new home for all your private photos. The photos you’ve shared on Google+ are still available in the photos tab of your Google+ profile.”
You can still go to Google+ Photos using this link: https://plus.google.com/photos/highlights, but I don’t know for how long. Most likely, Google+ Photos will disappear soon.