Seaside Course is the first stage of the 2-player Bobsled Race mini-game in Sonic Heroes. Like with the other dedicated stages, players race three laps around the stage in Bobsleds.
This course is based on the tropical ruins seen in Seaside Hill and Ocean Palace. Each lap begins with the bobsleds rolling across the beach, with lines of Rings to grab and Speed Boosters to hit for a speed boost and boxes that will slow down the bobsled that must be jumped over.
The bobsleds will reach a jump that launches the players into the interior of the ruins, which hold harmful spike balls that will throw characters off the bobsleds when collided with, followed by inclines that lead the teams up to the top of the ruins, eventually leading to a downward slope that leads back to the starting line. The boxes and downward slope have Item Balloons that requires teams to jump to be able to pop them.
Overall, this is a relatively simple course with few harmful hazards for a straightforward race.