Lower River Group - west side of Firehole River
When you enter the west bank of Firehole River at the steel bridge near Ojo Caliente, you encounter the first loose cluster of thermal features after approximately 100 m (110 yards). Largest and dominating feature is dark green Leaf Pool, a quiet hot pool with no geyser activity like all other members of the cluster.
Between Leaf Pool and the river Skeleton Pool is located. This is presumably the most dangerous spring of the entire River Group due to its deceiving overhanging rims. Skeleton Pool is listed in the RCN database as Buffalo Spring.
North of Skeleton Pool next to the river Crown Crater sits on top of a low sinter mound.
Around Leaf Pool several other hot springs can be found. Some examples are given below.
Upstream of Leaf Pool only a few, less remarkable springs are to be found until you reach the Mound Geyser cluster after approximately 200 m (220 yards). Already the first features north of Mound Geyser exhibit impressive sinter structures surrounded by crystal clear blue water. T. Scott Bryan listed these as UNNG-RVG-9, which is erupting together with Mound Geyser.
Mound Geyser itself outshines its neighbors with even more gorgeous geyserite globes around the rim. Mound's interval spans on average about 20 minutes, eruptions are up to 3.5 m (12 feet) high.
With LRNN033, Mound Cone and Fissure Cone further pretty springs are in the immediate vicinity south of Mound Geyser.
200 m (220 yards) farther upstream some more pools and unnamed geysers are located in the Upper River Group. These are to be described on this page later.