- There are still a lot of places we have to go.
- There are still a lot of places we have to go to.
I've asked some native speakers which sentence is grammatically correct, but they gave different answers. Two in three of them told me 1 is grammatically correct, but the rest told me 1 is wrong but 2 is correct.
I have no idea whose opinion is really right and why their opinions are different.
To my way of thinking, 1 is wrong, because a relative pronoun implied between places and we cannot be the adverb of "go". So, I think to make 1 grammtically correct, we should rephrase it as "There are still a lot of places for us to go".