Manby Hot Springs is inaccessible and on private lands with a special easement for conservation. There are no public or county roads to access this and the private roads are no longer permitted for traveling. The BLM has posted a sign and news release about this.
Legal public access to the Manby Hot Springs is by boat on the Rio Grande or through the trails accessed from the John Dunn Bridge, but not from the scenic easement on the rim.

If you’re traveling along the Rio Grande and find that the town of Arroyo Hondo, New Mexico, is on your route, you may want to schedule a stop at Manby Hot Springs, also known as Stagecoach Hot Springs. The area around Arroyo Hondo boasts two major hot spring attractions—Manby and Black Rock.
But what distinguishes Manby from neighbor Black Rock Hot Springs is the immediate location: Manby sits within the ruins of a rundown stagecoach stop, adding character to this attraction that makes for a memorable experience.

Primitive Hot Springs Pools near Taos
The pools can hold up to six soakers at once, and depending on the height of the river, the water temperature will likely remain around 97 F. But the most important thing to know about this particular attraction is that clothing is optional.
Many visitors to the springs, both at Manby and Black Rock, are without swimsuits. So this may not be the best option if you’re traveling as a family with small children. But Manby Hot Springs is less frequently trafficked than Black Rock since it’s a little harder to reach, so if you don’t care to encounter as many people, you may luck out and get the place to yourself.

As when visiting any hot spring attraction, you’ll want to bring your own towel, sunscreen, and plenty of cold water for rehydration afterward. If you plan on returning in the dark, you’ll also want to bring a flashlight. If you’re looking for refreshments en route, the tourist website for Taos, a nearby town, recommends Midtown Hondo.
Getting There

The hot springs are on the east bank of the Rio Grande, just southwest of Arroyo Hondo, west of Highway 522 North, and farther south from the Black Rock attraction. The only legal way to access is by boat on the Rio Grande River or hiking trails from the John Dunn Bridge.
Following the trail from the John Dunn Bridge will have you there in under an hour and about 3 miles.
If you’re traveling north on the highway, a left turn to County Road B007 will keep you moving straight ahead until the road hits a fork with a sharp right turn, at which point you should turn left, not right. (A right turn here will send you on your way to Black Rock instead.)
From here, maps indicate a fairly straight path to the Manby Hot Springs parking lot, at which point you just need to walk for one mile down a moderate hiking trail before reaching the actual attraction. Watch for the stagecoach stop to mark your arrival.
Details
Address: Arroyo Hondo, New Mexico, 87529 (near Taos)
Season: Year-round
Cost: Free