ANAHEIM, Calif. >> When California Adventure opened in 2001, it was a baffling disappointment. Fans of Disneyland, legion and devoted, eagerly sought a wild and whimsical sister-planet and instead found something that resembled theme park as learning center – far too much space was devoted to approximations of various California topography and businesses, far too little to rides. More important, there were few, if any references to the films and characters that turned Disneyland into the Happiest Place on Earth.

What Disney executives had hoped would make their Anaheim resort a multiday destination became too often simply the second half of a park-hopping day at Disneyland.

If the recent price increases don’t prove too big a hurdle, that should change this summer. Friday’s grand opening of the 12-acre, full-immersion and totally delightful Cars Land is the final piece of a five-year, $1.1 billion attempt to make California Adventure a fabulous full-day and into-the-night experience on its own.

There is also a re-themed entrance – Buena Vista Street, evoking the 1920s Los Angeles that Walt Disney might have encountered when he arrived as a nascent imagineer – and a wild nighttime Mad T Party in Hollywood Land. Both are lovely additions but it’s Cars Land that truly, and finally, pulls the park together.

Creating in loving detail the world of Radiator Springs from Pixar’s two “Cars” films, Cars Land is the most thoroughly realized land in the whole Disney resort. Walking down the forgotten bit of Route 66 that served as spine and theme of the first film – there’s Radiator Springs’ one-and-only traffic light, perpetually blinking yellow – it’s easy to forget you’re anywhere but here.

To the left is Mater’s Junkyard Jamboree, a swinging mini-Scrambler-like ride, followed by the bright orange Cozy Cone Motel, a semi-circle of Cone-cession stands. (The various fruit slushes should be a big hit, though I’m not sure about the dill pickle-flavored popcorn.) On the immediate right is Fillmore’s Taste-In, selling fruit and juices, followed by Sarge’s Surplus Hut and Flo’s V8 Cafe.

Behind it all, a wall of pine-studded red rock marks the land’s most ambitious ride – Radiator Springs Racers – and insulates Cars Land from the rest of the world with a re-creation of Ornament Valley. So vivid is the imagery that one 5-year old of my acquaintance, while standing in line for the Racers, looked up at rock, waterfall and bridge rising into the blue and asked, “So, wait, is the sky real?”

Now that’s altered reality. (And yes, the sky is real.)

Possessed of one of those deceptively long entrances that promise to be chockablock for months (the good news? at least half of it is in shade and there are FastPasses), Radiator Springs Racers is great fun, the perfect blend of imaginative dark ride and pulse-quickening speed. Splendid-looking race cars seat six (which means the single-rider line should also be a boon) and take you into the mountain and through another version of Radiator Springs before sprucing up either at Luigi’s Casa Della Tires or Ramone’s House of Body Art and sending you out to race another car (winners are random). It’s like Test Track at Epcot in Florida, only with “Cars,” much better stage craft (you could go on this ride a half-dozen times and still not see everything) and more fun.

Across the way is Luigi’s Flying Tires, which also has its structural roots in another Disney ride, the long-defunct Flying Saucers (the banner for which still hangs from Tomorrowland’s Innoventions building). A crazy cross between bumper cars and air hockey, Luigi’s puts riders in tire-shaped carts that are lifted by air jets (if you’re wearing a skirt, enjoy your Marilyn moment as you head toward your car) in a corral filled with oversized beach balls. The cars are guided by the riders’ movements – lean to the left, lean to the right – which makes Luigi’s a unique experience. A stop-and-start ride, the inevitable wait time may eventually outweigh the thrill factor, but it is the first and possibly only ride at an amusement park with physical fitness potential.

Like its films, Cars Land skews young, though not as young as the neighboring “a bug’s land” area, but even the more sedate Mater’s Junkyard Jamboree is twirly enough to please a jaded tween and teen (I brought one of each for this very purpose), both of whom joined the 5-year-old in giving Cars Land a hearty stamp of approval (and not just for the milkshakes at Flo’s, which are pretty dang amazing).

“This place finally makes sense,” said my 14-year-old son, referring to California Adventure as a whole. “Because ’Cars’ is both Disney and California.”

Which is absolutely right. With its paean to Route 66, Cars Land fits into the original vision while naturally adding the child-like fantasy (and branded merchandising opportunities) that designers have been infusing at different points throughout the park, whether by building Toy Story Mania, Ariel’s Undersea Adventure or giving the Mulholland Madness ride a paint job and re-christening it Goofy’s Sky School. All roads here now lead to inter-park reconciliation.

Like Main Street, the newly designed Buena Vista Street is nostalgic and stately (love the red trolleys), and though it references Los Angeles rather than Anywhere USA, its central statue of a young Walt and Mickey echoes the one that centers Disneyland.

With its fog machines, flashing lights and Tim Burton-ish feel, the Mad T Party also gives a Disney favorite its own unique spin: a more grown-up version of Alice that fits in perfect with the higher concept of Hollywood.

Walking in, the park does make more sense. Paradise Pier, with its roller coaster and bevy of attractions, may remain the alpha land, but there are many points of interest now. More important, with Cars Land, California Adventure at long last has a heart.