Clifton Gardens Reserve is a heritage harbour beach and picnic precinct on the eastern side of Mosman, backing onto the steep sandstone headlands of the Sydney Harbour National Park between Chowder Bay and Balmoral Beach. The reserve is best known for its two historic seawater swimming enclosures: the rectangular 1930s steel-framed Clifton Gardens Netted Pool stretching out from the sandy beach, and the circular concrete Thomson's Baths tidal pool built into the sandstone rocks at the southern end, both of which remain open to public swimmers year round. The grassy upper reserve lawns are terraced down to the water and are famous for their multi-level shaded picnic shelters with harbour views, which are often booked out for children's birthday parties and corporate events on weekend afternoons in summer.

Dog access at Clifton Gardens Reserve is heavily restricted by Mosman Council to minimise conflict with families using the swimming pools, playgrounds and picnic lawns, and the rules are amongst the strictest of any harbour reserve in Sydney. Dogs are only permitted on the beach, sand and reserve lawns on weekdays only, and even on weekdays access is confined to two narrow time windows: before 9:00am in the morning, and then again in the evening after 4:00pm during the non-daylight saving months from April to September, or after 6:00pm during daylight saving from October through to the end of March. Critically – and unlike neighbouring Sirius Cove, Taronga and Balmoral – dogs are PROHIBITED from entering Clifton Gardens Reserve AT ALL TIMES on Saturdays, Sundays and all public holidays without exception, even on-leash, and rangers patrol the car park and beach access paths actively from 8am onwards on weekends issuing on-the-spot infringement notices to any owners attempting to bring dogs inside the reserve fence line.

Facilities within Clifton Gardens Reserve include the two swimming enclosures, a toilet and shower block behind the main kiosk, the heritage listed Clifton Gardens Hotel kiosk building with takeaway coffee and snacks on weekends, three large covered picnic pavilion shelters, a fenced children's playground with climbing frames and swing sets, over 40 electric and wood-fired public barbecues, shaded bench seats at every terrace level, and a large metered on-site car park with disability accessible spaces directly off Morella Road. Several on-leash headland walking tracks start from the northern edge of the reserve car park and link through Sydney Harbour National Park to Chowder Bay, the Middle Head military fortifications and the Georges Head battery lookouts, so you can still enjoy a weekend dog walk in the area as long as you stay on the national park tracks outside the Clifton Gardens Reserve boundary fence itself.