First Mining Gold Corp. provided an update on exploration activities at its Birch-Uchi Greenstone Belt ("BUGB") Project located in the Red Lake Mining District of Ontario, Canada, near the Company's Springpole Gold Project (" Springpole"). First Mining has commenced a district-scale exploration program as part of a multi-year strategy to unlock the exploration potential on the +70,000-hectare property position located in the underexplored BUGB.

The mineral tenure comprising the BUGB Project surrounds Springpole, which was advanced to a Pre-Feasibility Study that was completed in January 2021 and contains an Indicated Resource of 4.6 Moz Au at 0.94 g/t and additional Inferred Resource of 300 koz Au at 0.54 g/t, including Probable Reserves of 3.8 Moz Au at 0.97 g/t, as set out in the technical report entitled "NI 43- 101 Technical Report and Pre-Feasibility Study on the Springpole Gold Project, Ontario, Canada", which was prepared for First Mining by AGP Mining Consultants Inc. ("AGP") in accordance with National Instrument 43-101 Standards of Disclosure for Mineral Projects ("NI 43-101") and has an effective date of January 20, 2021. First Mining is currently advancing Springpole toward a Feasibility Study. The BUGB exploration work programs have included widespread initial screening campaigns comprised of geochemical, geological, and geophysical surveys over key transects and favourable exploration features of the BUGB property setting that include components around structure, lithology, and mineralization.

The Company's exploration team has also been actively completing data acquisition that is targeted across the project area in a first ever district-scale regional program that aims to establish priority targeting at a meaningful and modern scaled approach. total of 537 samples were selected for analysis with only a portion returning significant or anomalous results. The results as listed include all samples received to date >2 g/t Au, with additional samples returning values below this threshold, or below detection limits (5 ppb).

Easting and northing coordinates for samples are Universal Transverse Mercator (UTM), NAD83 datum.