Cyclocross is a unique blend of bicycle racing formats. The course usually includes a mix of grass, dirt, sidewalk or short pavement sections, a couple of barriers about 16″ high that are designed to require dismounting and jumping over the barrier, and often either a sand pit or muddy section. The course is usually over 90% riding, with just a couple of barriers or short hills too steep to ride. A city park makes a great course, using grass and dirt trail sections for most of the race, with shorter sections of high speed sidewalk. The course is a short circuit, 1-2 km in length, and is repeated for 20 to 75 minutes of racing, depending on skill levels. This racing is probably the most spectator-friendly of all the bicycle racing disciplines, as the short laps through a park like environment often allow more than half of the race to be seen from a single spot.
The fitness of road racing and the handling skills of mountain biking are both useful in cyclocross. This is intense, high heart rate racing, akin to criterium racing. The mix of surfaces, barriers, and short runs require both skill and fitness. This is a mass start event, and almost always starts and ends with a full effort sprint. In between, drafting skills can be utilized, although it is not unusual to see solo breakaways succeed.
A road racing style bike is usually used, with the addition of somewhat wider tires to accommodate the mixed surfaces. Cantilever brakes are useful for courses that have any significant amount of wet sections. Cyclocross specific bicycles will have a bit higher bottom bracket, somewhat lower gearing than road bikes, and usually will have somewhat beefier construction, particularly forks. Some very successful cyclocross racers ride lightweight mountain bikes, usually without suspension forks, and with 1.5″ or narrower tires. Mountain bike shoes and pedals are usually worn, as the dismount sections require short sections of running.
Texas and New Mexico have annual cyclocross series, and both states offer age-based and skill-based state championships.