In the upper right corner of this image you can see the south shore of Sinus Iridum. These other features in this image are often missed because of the grandeur of the Sinus. Look over near the left edge at the mound, Mons Rumker (70km dia.) a large volcanic formation. Expand the image and you can see some of the individual domes that make up this large bulge in the lunar surface. It only rises about 1300m from the surrounding mare so you have to catch the light just right to get a good image.
On the right half of this image is a large peninsula of highland material extending down from the Sinus. Above center is Mairan (41km). The land above Mairan is a totally different texture than that around and below due to the Iridum impact. At the bottom of the peninsula on the right side, are some more large domes. The whitish one is Mons Gruithuisen (grooth-whee-zen) Gamma some 1740m in height and a diameter of 19km. Just above it is a much smaller little bump, listed in the Lunar Domes Atlas as Gruithuisen 3 only 1020km in height and 7.5km diameter at its base. Then the third one, next to the small crater Gruithuisen B (9km) is Gruithuisen Delta, a dome some 1900m high and 27km diameter, though it is oblong. A wonderful lumpy region on the Moon!
