Two rock horns stand up from the desert floor beside the road, close together and slightly tilted, and anybody who has ever seen a mule will recognise them instantly. The Mule Ears are the remains of volcanic dikes, sheets of molten rock that forced their way into cracks in the earth millions of years ago, hardened, and were then exposed as the softer rock around them wore away. They rise roughly a thousand feet above the surrounding plain and dominate this section of Big Bend National Park's Ross Maxwell Scenic Drive.
The viewpoint is an easy stop, with a parking area and a short trail that leads out across the desert toward the peaks and a small spring tucked into a fold in the hills. In the right season you will find a patch of green and a trickle of water that seems almost miraculous after the dry miles. The trail is a few miles round trip, with little shade, so it is best in the cool of the morning. Lizards scuttle, roadrunners cross the road and, at dawn and dusk, coyotes and javelinas are about.
Riding here is a gentle, flowing joy. The Ross Maxwell Scenic Drive curves between volcanic hills with long straight sections, short climbs and the occasional dip where a desert wash crosses. The tarmac is generally good, and the traffic is light. Wind can be strong, and flash floods in the summer rains can leave mud and debris on the road. In midday sun the heat is intense, so take your breaks in the morning or evening, and carry plenty of water. Winter mornings can be cold enough for gloves, but by noon the sun has warmed the rock.
The area has a long human history. Native peoples lived and travelled along the Rio Grande for thousands of years, and in the early twentieth century ranchers and farmers settled here, with a small community at Castolon, a short way further on. The old trading post there is now a seasonal store, and border raids during the Mexican Revolution brought US cavalry to Castolon around 1916. Today the river is quiet and shallow, and the Mexican hills on the far side are as empty as the Texas ones.
Fuel and food are not available at Mule Ears. The park fuel station at Panther Junction and the town of Study Butte, outside the west entrance, are the sources, and Terlingua nearby has a few more services, including a ghost town with a famous porch. Fill up, because the drive is long.