In a sense, we are already time traveling into the future, one second at a time. Plus, I think it has been sceientifically proven that an object traveling at high speeds ages more slowly than a stationary object. Theoretically, this means that if you were to travel into outer space and return, moving close to light speed, you could travel thousands of years into the Earth's future.
But in the sense you're probably implying, no, I don't think time travel is possible. My thoughts are similar to yours in this respect. The past was, but exists no longer; the future will be, but does not exist yet. It is impossible to travel back into the past, and impossible to travel to an exact point in the future without experiencing the time it takes to get to that point. Even an person circling Earth at the speed of light will still experience the time it takes to circle the Earth, albeit it would be at such an accelerated rate that the time past would go unnoticed.