Sanatorium Lake, nestled within Macedon Regional Park near Mount Macedon, Victoria, is a serene man-made lake surrounded by lush alpine ash and eucalypt forests. Constructed in the late 19th century to supply water to a proposed tuberculosis sanatorium—which was never built—the lake now serves as a tranquil destination for nature enthusiasts.

Visitors can explore the area via the 2.8 km Sanatorium Lake Eco-Trail, a gentle circuit that meanders through diverse vegetation, including tall eucalypts and fern gullies. The trail offers interpretive signage and opportunities to spot native wildlife such as kangaroos, wallabies, and over 150 species of birds.

The lake is accessible from Lions Head Road, with nearby picnic facilities at Days Picnic Ground and Sanatorium Picnic Area. While swimming and fishing are not permitted, the area provides a peaceful setting for picnics, photography, and leisurely walks.