Surface Features (4) . . .

The surface of Venus is rather smooth in many places, though not nearly as smooth as originally expected. However, we find evidence for many of the same geological features found on Earth: canyons, volcanoes, lava flows, rift valleys, mountains, craters, and plains.
Mountain Ranges
Venus has high mountains, many of which appear to be volcanic in origin. The adjacent image shows a portion of western Ishtar Terra that includes a high plateau, Lakshmi Planum, surrounded by four mountain ranges (white and red indicate the highest and blue and green the lowest elevations). The highest mountain range on Venus is Maxwell Montes, which can be found to the right of the Lakshmi Planum. It is in fact the highest mountain range in the Solar System, reaching an elevation of 11 km above average elevation (2 km more than the elevation of Mount Everest above sea level on Earth). Some other mountains are shown in images below.

Presently Active Volcanoes?

Indirect evidence from periodic increases in the concentration of sulfur dioxide in the atmosphere and the detection of lightning in certain regions suggests that volcanoes are presently active on Venus. It is also thought that the haze layer in the atmosphere may be replenished by particles from currently erupting volcanoes. However, all such evidence for active volcanoes is circumstantial at this point. Here is a discussion of volcanoes on Venus.

Volcanoes and Lava Flows
Venus appears to have more volcanoes on its surface than any object yet examined in the Solar System, and there is strong evidence that volcanoes have erupted on Venus in the geologically recent past (see the adjacent box). Here is map illustrating the location of volcanoes on Venus.

An example of a large volcanic complex on Venus is Beta Regio, which is associated with a major fracture zone southwest of Ishtar Terra and contains two large shield volcanoes, Theia Mons and Rhea Mons. One piece of evidence for recent volcanic activity is the presence in many regions of features that look like relatively new lava flows. The two images shown below illustrate a volcano about five kilometers in diameter near Paragon Chasma, and an image of apparent recent lava flows in the Sif Mons region.