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We report on electrokinetic manipulation of submicron particles in a device with microfabricated Si electrodes featuring segmented sidewalls acting as tracks guiding particles under hydrodynamic drag. Electrohydrodynamic drag, both AC electroosmosis in low-conductive medium and electrothermal flow in high-conductive medium, gives rise to fluid rolls that deliver particles to tracks where they are held under the influence of dielectrophoretic forces. Particles are being railed along tracks under pressure-driven flow to a downstream junction where tracks act as bridges, keeping particles on course within the main channel causing their post-junction enrichment. This outcome, however, is strongly coupled to electrode sidewall contours as demonstrated here. We also report on particle oscillations under strong AC electroosmosis. Specifically, particles in deionized water can be seen bouncing off tracks or circulating with convective rolls in and out of space beneath tracks at an oscillation frequency and amplitude depending on the activation frequency. These results collectively draw attention to the functional use of electrode sidewall contours for continuous-flow manipulation of particles, which are rarely explored in microfluidics and yet could lead to more effective designs for particle separation and enrichment.