Surf, Sea, and Sand is the fourth Challenge Act of Seaside Hill Act 2 in the console/PC version of Sonic Generations. It is unlocked after clearing every Stage in the Dreamcast era and is playable only as Modern Sonic.
This Act takes place within a highly modified version of Seaside Hill Act 2, where the player will tackle all three different pathways before reaching the Goal.
The player begins on a a platform in the water, connected to another platform directly in front of it. The player must then use the Homing Attack on a Balloon to cross the gap between the platform and a giant Sea Turtle. After navigating across a number of platforms, the player will be taken to an island via a spring, and must defeat a group of Egg Pawns before climbing up a large, vertical tower of pillars. At the top, the player will be launched into the racetrack section, where they must drive the go-kart while evading bombs and pillars of flame. The Goal Ring can be found at the end of the track.