Suncor Energy Inc’s oil sands operation north of Fort McMurray, Alberta, has been in production since 1966. Pond 1A, a fluid fine tailings (FFT) storage and flow-through recycle water pond, began infilling in the 1970’s. The first sampling programme of the FFT was conducted in 1977, with periodic follow-up programmes through to 2010. This pond has been used to store volumes of FFT in the form of Mature Fine Tailings (MFT) at significant depths in relatively undisturbed conditions for over 25 years. This site, unique in the industry, is important to understanding the long-term behaviour of fluid fine tailings in the oil sands landscapes. The observed behaviour provides insights into potential storage and material strength gain projections. Several decades worth of sample profiles are provided, along with general observations on the potential implications to the industry.