They are as much a part of Old Sacramento as cobblestone streets and riverboats.
But the carriage horses that for decades have clopped through Sacramento's historic downtown district would go the way of the Pony Express if animal activists achieve their goal.
A loosely organized group known as Working Animal Advocates has launched an aggressive campaign to ban the carriages from Old Sacramento, arguing that forcing horses to pull heavy wagons amid traffic, tourists and inclement weather is abusive.
Similar battles are being waged across the country, including in New York City, where Central Park's iconic carriage horses have become a talking point in the mayoral race.
"This is inherently an inhumane environment for horses," said Kim Flaherty, a Bay Area activist leading the Old Sacramento campaign. "We understand that the city is trying to capture a historical ambience. But seeing horses working in these conditions is very troubling to me."
Her group's campaign includes an online petition drive, picketing in Old Sacramento and letters to public officials. In response, the historic district is working to revise a portion of the city code designed to protect carriage horses.
"The code could use some tweaks," said district spokeswoman Liz Brenner. "We want to do the right thing, offer the horses an additional measure of comfort," including more shade and additional breaks.
But Brenner ruled out the idea of banning the carriages altogether. "Over my dead body," she said. "I won't let it happen."
In her corner are organizers of the "Save the Carriage Horses of Old Sacramento" campaign, who also have begun gathering signatures.
"The public loves these horses," Brenner said. "They are absolutely part of the ambience of Old Sacramento."
Flaherty's group, which has been documenting the working conditions of the horses in recent months, contends the city has failed to enforce codes designed to ensure their safety, including offering them frequent water breaks in shady areas and barring them from working in triple-digit heat.
The city code states that the animals should not work when a thermometer placed at street level exceeds 100 degrees. But the thermometer used to gauge temperatures in the district is more than 13 feet from the ground, under the shade of a balcony, Flaherty said.
"It doesn't reflect the temperature where the horses are working," she said. "It's a difference of 5 to 10 degrees."
Flaherty's group claims the horses do not always get mandated breaks during their shifts hauling tourists around the district in wagons that weigh 600 to 800 pounds, and that when they do they often are left standing in full sun.
While the campaign focuses primarily on the welfare of horses, Flaherty said the carriages also put the public at risk. Drivers slowed by the carriages sometimes use aggressive maneuvers to get around them, she said, and horses have been spooked by dogs, loud music and other distractions.
Dianna Newborn, whose family has operated horse-drawn carriages through Old Sacramento for more than two decades, said she can recall only a handful of incidents in which carriage horses, drivers or members of the public were in jeopardy. Occasionally, she said, dogs have attacked horses. Once, a drunken driver struck a carriage.
Her family's Top Hand Ranch is one of two carriage operators that serve Old Sacramento, charging $10 per carriage for rides around the district. The company, which features large draft horses as well as retired racehorses, also participates in special events, including a wagon train ride from Nevada to Placerville.
Newborn and Brenner said they were unaware of any carriage incident that seriously injured animals or people in Old Sacramento. Newborn said Top Hand Ranch takes pains to make sure its horses are comfortable and safe.
"I don't like seeing either horses or people mistreated," she said. "We've always had animal rights people who oppose us, but this is extreme. I don't feel it's justified."
UC Davis equine veterinarian John Madigan, who is certified in animal welfare, agreed. Madigan said horses in general are "physiologically adapted to working," even in hot weather, and the Old Sacramento teams are well trained and monitored.
"I think those horses have it pretty good," Madigan said. "They're more protected than Caltrans workers. I have never seen them in situations where they are in distress. I don't see any major risk to horses or the public."
Carriage horses have sparked controversy in other urban areas, with cities in Florida, Nevada and New Mexico, among others, banning the trade. The Humane Society has supported legislation to phase out horse-drawn carriages. People for the Ethical Treatment of Animals has published a lengthy list of incidents involving horse-drawn carriages, including one in Burbank earlier this year in which a woman suffered a head injury after a spooked horse caused the vehicle to overturn.
In New York City, mayoral candidate Christine Quinn has become a target of animal rights advocates because of her support of horse-drawn carriages in Central Park. One of her rivals in the Democratic primary has promised that, if elected, he would ban the famous carriages.
Brenner, of the Old Sacramento Historic District, said she is busy trying to allay concerns. She is placing thermometers in new areas to gauge temperature conditions, and she said she will push for additional water stations and better code enforcement. She plans to take her suggestions to city officials, she said.
But the changes may not be enough to satisfy animal activists.
"As long as these horses are forced to pull carriages in extreme temperatures, navigate congested traffic conditions, breathe in exhaust fumes and pound hard city streets that are damaging to their legs and feet, then we will seek a ban," Flaherty said.
"It's a noisy, stressful, unnatural environment that they shouldn't have to endure just for some gimmicky tourist attraction that is anything but nostalgic or historically accurate."
Call The Bee's Cynthia Hubert, (916) 321-1082. Follow her on Twitter @cynthia_hubert.