At the moment, Third Street is the third station from the end of the line at Seventh Street. It is elevated above street level and from here, there is a short walk and a few steps (also a ramp) to access the Epicenter shopping/entertainment complex.
Like other stations in the Uptown area, you can walk from here to the next one if it's easier than waiting for the next train. The station is located between the Stonewall station and the Convention Center/Arena station.
I would not recommend this station for access to either the Arena or the Stadium, but it is useful if you're headed to the NASCAR Hall of Fame.