Many zones in Sonic the Hedgehog 2 feature multiple pathways, some of which are hidden or require specific actions to access. These hidden paths often lead to shortcuts, large caches of rings, power-ups, or even secret areas. Exploring every level thoroughly is key to uncovering these secrets.

Tips for Finding Secrets:
- Look Up and Down: Don't just follow the main path. Many levels have verticality, with hidden routes above or below.
- Breakable Walls: Some walls or floors can be broken with a Spin Attack or Spin Dash, revealing new areas. Look for subtle cracks or different textures.
- Springs and Boosters: Use springs and speed boosters to launch yourself into unexpected areas. Sometimes, a seemingly random bounce can lead to a secret.
- Waterfalls and Background Elements: In zones like Aquatic Ruin or Mystic Cave, look behind waterfalls or at suspicious background elements; they might hide entrances.
- Tails' Flight: If playing with Tails, use his flight ability to explore high-up areas that Sonic cannot reach alone.
Replaying levels and experimenting with different routes is the best way to discover all the hidden paths and shortcuts, which can drastically improve your completion times and ring count.