The Mongarlowe River flows through the Monga National Park region of New South Wales, in the Queanbeyan-Braidwood area. The river is gently flowing in its upper reaches near Monga, where it passes through wooded country over a partly sandy bed. The landscape alternates between hilly terrain and flat sections, with narrow, tree-lined races characterizing much of the river's character.

The Mongarlowe River is perhaps most relevant to paddlers as a tributary of the Shoalhaven River. One practical option is to put in at the Mongarlowe River Bridge and paddle approximately 3 kilometres downstream to the Shoalhaven junction, though this requires seeking permission from the property owner on the southern side of the Mongarlowe bridge. From that junction, paddlers continuing downstream on the Shoalhaven toward Oallen Ford will encounter Grade II and Grade IV rapids, with the Grade IV featuring two drops before a final one-metre chute running diagonal to the riverbank — this rapid warrants inspection before running, with portaging best accomplished on the right bank.

The river and surrounding national park are known for wildlife, including platypus, which can be spotted swimming in the water. The area is also notable for birdwatching, particularly in October and November when Monga and Gippsland waratahs flower and attract birds and insects. The Mongarlowe River picnic area at 715 River Forest Road, Monga NSW 2622, provides picnic tables and access to the Waratah walking track along the river.

For paddlers approaching the Mongarlowe as part of a longer Shoalhaven trip, the section from Charleyong to Oallen Ford covers 29 kilometres and is described as an easy two-day paddle or one long day, with campsites described as plentiful along the way. The car shuttle for that broader section is 42 kilometres one-way via Nerriga Road.