No, not at this moment. They don’t allow stations to be used more than once on a single route. I do hope they allow it though. A ring line would be cool to see.
The sandbox is only a playground to start the game quick and dirty without any consequences for non-compliance with traffic rules,... if you want. But If you want to play more seriously, you have to use the career mode. In career mode, you can build any line according to the laws of reality with every Tram that you have "by" from the market, however you want. You can build a circular line include endpoints as "normal" stops. All possible stops can be served by different lines on a part of the same line.For example, I´ve 3 lines coming from different directions, but in the citycenter I use three stations for changing trains at the same time.However, every line must start or end at an endpoint in any direction. Just like in real life. Try it.
