Walking through Horton Plaza is like watching Sir John Gielgud in a Thighmaster commercial - it's sure as hell a brilliant performance, it generates a lot of attention, you couldn't ask for better technique, but underneath there's always that unpleasant subtext. Horton Plaza is only a shopping mall. Its purpose and physical logic is like any other mall.

But it's brilliant. But it's a mall.

Yeah it's both and although it makes me miserable to admit it, it's also a tourist attraction.

Horton Plaza is a complicated 5-level outdoor shopping mall located right in downtown San Diego, cutting a sort of diagonal swath through five or six blocks of downtown San Diego real estate, adjacent to the city's historic Gaslamp Quarter. Anchors are Mervyn's, Nordstrom's, Macy's, a big Sam Goody, Planet Hollywood, and connected to a Westin Hotel and the Balboa Theatre under restoration.

But the main attraction is the pedestrian theatre. It's one of those things you might glimpse from a distance and a trigger in your head goes, "What the hell is that?" and you find yourself drawn in that direction.

You walk through, like, a little canyon, a five-level fissure with familiar retail stores on either side, but unlike the dull spatial rhythms in a regular mall which encourage anaesthetized sleepbuying, Horton Plaza gives you surprises, bright colors, architectural tricks, odd spatial rhythms and new views with every step. The levels on each side don't match each other, and there are long one-way ramps and sudden dropoffs, dramatic parapets and shadowy colonades and cul-de-sacs, and these brightly painted facades stand up as if from nowhere.

These fragmented spaces look and feel more like a postmodern art project than a serious mall. It's like this place was half-shuffled by an earthquake and they just repainted without major repairs. Like a three-dimensional puzzle, mind games with the architect. It is damned interesting.

Horton Plaza broke all the rules of traditional mall management.

No, I take that back. It didn't break all the rules, but it broke an important rule.

A shopping mall is a retail revenue generation machine, a high-performance one but also a high-maintenance one. Mall management has been a well-researched branch of the science of consumer behavior, separating you from your disposable income, ever since Victor Gruen invented the shopping mall in 1956.

In Gruen's days, signing up larger department stores as anchors was necessary for the financial stability of the project, and to draw retail traffic that would result in visits to the smaller stores in the mall. Anchors generally have their rents heavily discounted, and may even receive cash inducements from the mall to remain open. (Did you know the mall would actually pay the anchor to stick around?) In physical configuration, anchor stores are normally located as far from each other as possible to maximize the amount of traffic from one anchor to another.

Beyond the anchors, the other retailers are not only carefully selected but carefully mixed and sequenced. No bail bondsmen. No tattoo parlors. No non-chain independent stores, unless this particular mall is in trouble.

The toy stores and book stores don't get slotted too near other other, and it must be a constant struggle to keep the shoe stores from bumping. More shoe stores than any other retail presence. No clothing stores next to restaurants, because the smell of food is bad for business. Jewelry stores get the coveted spots in the corners, with their multiple entrances and double window display space, because jewelry stores have relatively high sales per square foot. Toy stores and book stores and especially sporting-goods stores have the lowest sales per square foot. The reliably highest, surprisingly, is the food court.

There are a thousand aspects of accumulated architectural-psychology traditional wisdom reflected in mall design and store design, including traffic patterns, spatial choices, mirrors, sightlines, lighting and glossy reflective surfaces, aspects of the audio environment, not to mention the less tangible psychological workings of brand identification and consumers' fantasy-identification with the faces they see. Paco Underhill makes a living out of observing these effects and improving them. He calls it 'retail anthropology' and has written two books on the subject. Although it's a science, there's still lots of room for improvement.

Up until Horton Plaza, there was another rule: malls must be boring.

To say that shoppers are spatially manipulated in malls is to make a wild understatement. I mean, obviously. J. Crew and Foot Locker and bebe and the Sunglass Hut and Brookstone love you but prefer you in a drifting, semi-conscious trance, exposed to maximal merchandise, the better to separate you from your numbers.

You are in a trance.

The moment when that trance state takes hold is called the Gruen Transfer. Victor Gruen would have been mortified; he was an Austrian, a socialist, and developed the mall as a way to re-integrate economic life and civic life. Victor Gruen created a monster. Unconsciously influenced by accent lighting, ambient sound and music, spatial choices, visual detail, mirrored and polished surfaces, climate control, the sequence and order of interior storefronts, all of this, the consumer's decision-making consciousness subsides and he or she becomes an impulse purchase looking for a place to happen.

The effect is extensively documented, reliable, observable, and marked by a slower walking pace and glazed eyes.

It was thought that the corridors of the mall environment, the place where the merchandise isn't, always had to be less attractive and interesting than the store interiors, where the merchandise is.

It was thought for the trance to work properly, the mall had to lower "ambient arousal levels". Malls had to be boring. This was more than a matter of taste. C'mon. There's money involved.

Horton Plaza was the $140M centerpiece of a downtown redevelopment project run by the Ernest Hahn Company. Hahn gave the job to Jon Jerde. After 13 years in the mall business working for others, this was Jerde's first big break.

When it opened in August 1985, it was a risky and radical departure from conventional wisdom. By making the mall an attraction in itself, Jerde stood the conventional wisdom on its head.

What was the result of breaking the boring rule?

As the first example of Jerde's "experience architecture", Horton Plaza was an instant financial success, with 25 million visitors in the first year. Twenty years after opening, it continues to generate San Diego's highest sales per square foot, in the range of $600 to $700. From an urban planning standpoint, Horton Plaza is a civic asset that generates pedestrian traffic and shares it with a number of contiguous destinations, paving the way for the revitalization of the Gaslamp District. According to its web site, the mall has been "hailed locally and nationally as an overwhelming success since its opening in August 1985, winning dozens of awards in design, architecture and urban development."

The Jerde Partnership went on to design the gigantic $680M Mall of America in Bloomington, Minnesota in 1982, the Los Angeles 1984 Olympics, the outlandish and synthetic urban experience Universal CityWalk and the (original) pirate show (not the one with the pirate whores) and (the original) (and better) facade of the Treasure Island Casino in Vegas in 1993, the Las Vegas Fremont Street Experience in 1995, and more recently a string of important projects in Japan and China.

Jerde's projects are consistently marked by three things: a respect for user experience unique among American architects, a lasting sense of clarity and fun in the final result, and a very high rate of return. In the first twenty days of operation, the Las Vegas hotel/casino Bellagio that Jerde designed for Steve Wynn achieved an astronomical annualized sales of $1800 per square foot. In the architectural community Jerde has been an outsider, widely critized for commercialization and artificiality, but his impact on the profession is increasingly hard to ignore. As of 2005 he might be the single most successful architect on the planet.

That's what you get for breaking the rules.