Niantic Labs Field Trip app for Google Glass has received an update that enables voice controls. And all you have to say is "Okay Glass, Explore Nearby" to kick Field Trip into high gear. Field Trip hit Google Glass back in August of 2013, and it's just now getting support for those voice commands that typify Glass.
So what took so long? Despite Google Glass supporting voice commands, it was only recently that third party apps gained the ability to work with those voice commands as well.
If "Explore Nearby" isn't enough for you, you can take Field Trip on Glass and get more specific and look specifically for instances of notable architecture, history, art, food, and the generalist category of "Cool Stuff".