The San Antonio River Walk is saving me from obesity.

I've been eating my way across the city for four days now, enjoying the best of San Antonio's food during the annual Culinaria celebration. The events have included elaborate lunch and dinner affairs, a Mexican tasting event and a fancy soiree that featured some of the area's leading chefs offering small bites of their very best dishes. Needless to say, I've consumed more calories than my body has required.

After all of this eating, my waistline would be expanding rapidly were it not of the San Antonio River Walk. I've been stayinig at the beauiful Westin hotel, located right on the River Walk in the heart of the scenic downtown district. The San Antonio River and the charming district built up around it may be the most iconic image of San Antonio (save for the Alamo itself), and it makes an ideal place for visitors to stay, eat, shop and explore.

It's also an ideal place to excercise. The river winds through the downtown and neighborhoods such as La Villita, which give it a distinctly Mexican ambiance. Along both sides of the water, the River Walk offers paved pedestrian access, where visitors can stroll alongside the river and well-landcaped gardens that run along either side. Though the weather is already heating up for the summer, the River Walk provides a welcome respite from the heat, so I've been taking advantage of the setting to run a few miles each morning before beginning my touring for the day. Along the way, I pass plenty of other walkers and runners.

The River Walk is San Antonio's best toursim asset, and the city has gone to great effort to expand it in recent years. An expession project currently underway has added several miles of walkable riverfront extending from the downtown area in either direction; when the project is finished, there will be more than 8 miles of walkable riverfront. The expansion projects allow pedestrians to walk north to the city's museum district, and south to the grand homes in the historic King William neighborhood.

Of course, running isn't for everyone, and the city offers other ways for visitors to experience the River Walk. Groups can take a boat tour of the downtown district, with guides who tell the history of the River Walk and point out some of the area's most interesting spots. River taxis also ply the waters through town, picking up visitors along the River Walk and ferrying them to wherever they want to go. There's even a lock system that allows the boats to ride up river to areas of higher elevation.

I think my morning runs along the River Walk are helping me stay in shape during this trip — or at least that's what I tell myself. Even if I'm not burning off all of the calories, though, I'm certainly enjoying the view.

A group explores the River Walk via boat.

The River Walk includes stone bridges, shade trees and great architecture.

Visitors can use the River Walk to access hotels and museums.

Today I donned an apron, toque and rubber gloves for an intense training session at the CIA. The mission: South American ceviche.

I'm not at Langley, but in San Antonio, at the "other" CIA — the Culinary Institute of America. The organization is recognized as one of the foremust culinary schools in the United States. In addition to its campuses in Hyde Park, New York, and Napa Valley, California, the school runs an outpost here in San Antonio, where students and professors specialize in food techniques from Central and South America.

In addition to training future chefs, the CIA offers a number of continuing education courses that are available to community members (visiting groups can arrange to take a class as well). Today, I joined a group of about a dozen other food enthusiasts for a hands-on class on South American ceviche. We entered the institute's brightly-colored Latin demonstration kitchen, where the staff had prepared aprons, toques (chef's hats) and recipe packets for us.

Chef Elizabeth Johnson-Kossick introduced herself as our instructor for the afternoon. A CIA professor, Chef Johnson-Kossick has spent large portions of time living in South America, and was intimately familiar with the details of the cuisine throughout the region. She spent a few minutes introducing us to the concept of ceviche — fresh fish flash-cured in lime juice — and teaching us about its different varieties in Columbia, Ecuador and Peru. She also gave us an introduction to some of the ingredients we would be using, such as striped bass, shrimp, Mexican limes and plantains.

After the overview, we split up into four smaller groups to prepare a variety of ceviches in the well-outfitted instructional kitchen. Each team got a specific recipe to work from, along with a tray full of all the ingredients and tools we would need.

My team was tasked with making two ceviches — an Ecuadorian-style shrimp ceviche and a Colombian-style ceviche with striped bass and coconut milk. Chef guided us through the steps of mashing garlic cloves into paste, cutting cubes of fish and combinging the multitude of ingredients to taste. It was amazing to watch as raw fish cured into a safe, edible food after just a few minutes of marinating in the lime juice.

After an hour or so of hard work, the teams reconvened to sample all of the different ceviches we had made. We topped the five different dishes with some traditional South American ingreidients, including chopped peanutes, fried plantains, toasted coconut shavings and popcorn. Each variety of ceviche brought its own blend of flavors and textures, but they were all cool, delicious and remarkably fresh.

One afternoon at the CIA didn't turn me into a world-renowned chef, but it did give me and my compatriots an introduction to a new favorite food, and the courage to try the recipes out at home.

Chef Johnson-Kossick gives an overview of South Ameican pepers.

Ahi tuna "tiradito" — a sashimi-style raw fish dish.

My plate of four ceviches and a fried plantain chip.

Sometimes a good meal can take you places. Today, brunch transported me from Texas into the colonial heart of Mexico.

I'm in San Antonio for a few days doing research for an upcoming magazine article. It just so happens that my trip coincides with Culinaria, a four-day foodie event that highlights some of the best flavors of San Antonio and the Texas Hill Country. So in addtion to visiting tourist spots like the River Walk and the Alamo, I'm taking advantage of some of the delicious opportunities that Culinaria offers.

The events at Culinaria range from large-scale gourmet tasting fairs to small, intimate winemakers dinners. Today's event might be my favorite of all. Called "Sabado at Casa Herman," this small brunch took place in an intimate new restaurant called Casa Hernan. The restaurant is owned by chef Johnny Hernandez, who has made a reputation as one of San Antonio's foremost purveyors of authentic Mexican cuisine. This new restaurant is located in the ground floor of Hernandez' personal home, and features architecture and artwork that you would find in many of Mexico's colonial towns.

Hernandez hosted this "Sabado" (or "Saturday") event to showcase one of his favorite styles of Mexican cuisine — traditional barbecue. Unlike American barbecue, which focuses on pork prepared in large smokers, Mexican barbecue features lamb and beef, which are smoked for hours in holes dug in the ground. A traditionalist, Hernandez dug pits in his own backyard to smoke the lamb and beef head that he served for brunch. As several dozen guests arrived at the event, Hernandez took them each out back to show them his barbecue pits and explain his traditional techniques.

Barbecue was the highlight of the brunch, but certainly not the only component. Our brunch buffet featured many other classic Mexican dishes, including tamales from Oaxaca and Veracruz, black-beans hand-made tourtillas and black beans with queso fresco. My favorite dish was the chilaquiles, a chicken and tortilla caserole traditionally served as a breakfast item in Mexico. The deep, complex and authentic flavors took me back 12 years and thousands of miles to my days as a student living in Morelia, a colonial Mexican city.

I ate as much as I could muster at brunch, washing it down with traditioanal "aguas" — Mexican fruit drinks made from coconut and guava — and finishing with colorful sweat bread pastries. For a blisfull noon hour on a May Saturday in San Antonio, I got to taste the best of Mexico all over again.

Traditional Mexian limes — a condiment for all occsions.

"Pan dulce" — Mexican sweet bread pastries

Authentic tamales wrapped in banana leaves