Classic Sonic's Act sees the half-pint hedgehog roll under barrels, bounce over Gun Beetles, swing from bars and catch the "Got Ring?" blimp in time to bounce his way over a wall. Most of the level layout consists of straightaways and a large number of slopes that Sonic can gain speed quickly from by rolling down them.
Modern Sonic's Act sees the present-day hedgehog grinding across the suspension rails of bridges and dodging Blue Eagles. The level is designed in a somewhat 3D environment where some routes are in-between others, so depending on what Sonic does, he will end up in either the foreground grinding on the bridges, the middle going through the middle of the bridge, or going into the background to avoid a platforming section. There are also hidden rockets that Sonic can use to take shortcuts with.
|052||Die-Hard||Clear Radical Highway Act 1 in 3:00.00 without losing a life!||2000 Illustration (Art)|
|053||Ring Collector||Collect 30 Rings in Radical Highway Act 1 in 1:00.00!||Live & Learn (Music)|
|054||Keep the Pace||Grab Time Items and clear Radical Highway Act 1 in time!||Unknown from M.E. (Music)|
|055||Rampage!||Defeat 11 enemies in Radical Highway Act 1 in 0:45.00!||Throw It All Away (Music)|
|056||Stealth Attack||Clear Radical Highway Act 1 in 3:30.00 without defeating enemies!||2001 Illustration (Art)|
|057||Special Trial||Defeat 3 Gold Beetles in Radical Highway Act 1 in 2:30.00!||Rouge (Model)|
|058||Perfection||Clear Radical Highway Act 2 in 5:00.00 without taking damage!||10th Anniversary Figurine (Art)|
|059||Ring Collector||Collect 75 Rings in Radical Highway Act 2 in 1:00.00!||Toxic Caves (Music)|
|060||Keep the Pace||Grab Time Items and clear Radical Highway Act 2 in time!||Palmtree Panic (Music)|
|061||Rampage!||Defeat 15 enemies in Radical Highway Act 2 in 0:30.00!||2002 Illustration (Art)|
|062||Stealth Attack||Clear Radical Highway Act 2 in 0:40.00 without defeating enemies!||Sonic Boom (Music)|
|063||Item Collector||Get all Item Boxes in Radical Highway Act 2 in 1:30.00!||2004 Illustration (Art)|
|064||Special Trial||Boost through Radical Highway Act 2 in 5:00.00!||Shadow (Model)|
|0:00.00 - 2:00.00|
|0:00.00 - 3:00.00|
- Of all the stages in Sonic Generations, this stage is the only one that Sonic was never playable in from the original game. Shadow the Hedgehog ventured through this stage instead.
- Even though Sonic was never playable in Radical Highway in Sonic Adventure 2 story-wise (he was playable on the multiplayer racing mode), he has been there at least two times: During the intro of Sonic Adventure 2: Battle and Mario & Sonic at the Olympic Winter Games (Dream Snowboard Cross).
- There's a large blimp in this level that says "got ring?", which is a reference to "Got Milk?", like in the original.
- It only appears in Act One however, making Classic Sonic the only one to interact with it.
- The Soap blimp is not present.
- The blimp from the hub world says "got ring?" while the one from Act One says "got rings?".
- In Act Two, there are some ads that say "Chao Soda" "Pizza Sonic 20: Anniversary!" and "Time Eater".
- There are also ads in Act One, although they are pretty well hidden, and the "Pizza!" ad is not present at all.
- The "Pizza Sonic 20: Anniversary!" ad is an updated version of the "Pizza Sonic 2" ad from the original City Escape.
- This is one of the two city levels in the Nintendo 3DS version of Sonic Generations, The other being Casino Night.
- Unlike City Escape, this level features Gold Beetles, and there are in fact more than one (as seen in a mission). In this game, they disappear almost immediately after appearing on-screen. Sonic needs to quickly homing attack them before this happens to reach a higher route.
- The remix for Act 1 was made by Cash Cash, while the remix for Act Two was made by Circuit Freq.
- Cash Cash's remix of Radical Highway Act 1 samples the beat used in their song "Obsessed".
- Despite it clearly indicating that the player must boost through the level, it is possible to complete the Special Trial mission for Modern Sonic without using the boost.
- On a similar note, it's also possible to S rank the second Act without using the boost. This is the only level where this is possible.
- This is the only Nintendo 3DS level in Sonic Generations where Classic Sonic can go into the background and foreground.
- Despite taking place in Radical Highway, the rival battle with Shadow does not reference the intro of Sonic Adventure 2: Battle, unlike its console counterpart.
- There are some signs saying "Route 00 Freedom ? Miles" around the level, just like in the original version of the stage.
- Radical Highway is the only stage on the Nintendo 3DS version to have a rival battle with a rival who went through the stage originally.
|"Radical Highway: Act 1 "Vengeance is Mine - Cash Cash RMX""||Cash Cash||3:25|
|"Radical Highway: Act 2 "Vengeance is Mine - Circuit Freq RMX""||Circuit Freq||2:43|
|"Rival Battle: Shadow the Hedgehog "For True Story (Short ver.) - Circuit Freq RMX""||Circuit Freq||2:20|
|"Rival Battle: Shadow the Hedgehog - Shadow Attack "All Hail Shadow (Short ver.) - Crush 40 RMX""||Crush 40||0:48|
|"Rival Battle: Shadow the Hedgehog - Sonic Attack" Live and Learn (Short ver.)"||Crush. 40||0:48|
|N/A (Hub world)||Jun Senoue||1:18|