My dad and I are in the middle of watching Stargate SG1 (as of this post, we're in the seventh season), and I thought it would be cool to draw the portal, the Dial-Home Device (DHD), and the unstable vortex that results when a Stargate is activated. There are several types of Stargates in the franchise - this one in particular being a second-generation Milky Way type. Other types include the first generation prototypes and the third generation Pegasus type. The main cast regularly took trips through the Stargate system for exploration and for defenses against the ongoing villain of the show: The race of parasitic symbiotes known as the Goa'uld (goo-ah-OOLD).
Sci-fi has come up with some interesting types of interstellar travel, usually involving a wormhole or some form of subspace dimension. Star Trek makes use of subspace with their dilithium crystal powered warp drive, Stargate uses both wormholes and subspace, and Babylon 5 uses a sort of combination of the two with its Jump Gate system. Theoretically, you could also use some sort of space-bending or 4D method.
For this picture, I looked up the specifics so that I could make an accurate drawing.