The Uranius group of volcanoes is located on planet Mars in the northeast part of Tharsis

Tharsis

The Tharsis region on Mars is a vast volcanic plateau centered near the equator in Mars’ western hemisphere. The region is home to the largest volcanoes in the Solar System, including the three enormous shield volcanoes Arsia Mons, Pavonis Mons, and Ascraeus Mons, which are collectively known as...

 and include Uranius Patera

Uranius Patera

Uranius Patera is a volcano on Mars located in the Tharsis quadrangle. It is about 3 kilometers high and it has shallow slopes. It belongs to Uranius group of volcanoes in the Tharsis area.Side of Uranius Patera consist of radial lava flows with few low shields with the large caldera which is...

, Ceraunius Tholus

Ceraunius Tholus

Ceraunius Tholus is a volcano on Mars located in the Tharsis quadrangle at 24.2 degrees north latitude and 97.4 degrees west longitude and it is a part of Uranius group of volcanoes. It is 130 km across, 5.5 km high and is named after a classical albedo feature name.It is generally...

, and Uranius Tholus

Uranius Tholus

Uranius Tholus is a volcano on Mars located in the Tharsis quadrangle at 2.9° north latitude and 121.6° west longitude. It is 101.7 km across and was named after a classical albedo feature name.- Volcanoes :...

.
They are dated to the Late Hesperian

Hesperian

The Hesperian is a geologic system and time period on the planet Mars characterized by widespread volcanic activity and catastrophic flooding that carved immense outflow channels across the surface. The Hesperian is an intermediate and transitional period of Martian history...

Epoch and are part of earliest phases of volcanism in the Tharsis province. All three volcanoes are interpreted as basaltic shields. The volcanoes of Uranius group were active for short periods of time (10 000–100 000 years) and are significally older than the major Tharsis volcanoes.