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Colorado hunting unit

GMU 121: public land and hunting map

GMU 121 is one of Colorado Parks and Wildlife’s 186 Game Management Units (GMUs) in Colorado. It covers about 1,049 square miles (671,458 acres), and roughly 4.2% of it is public land: state land 4.1%.

Measured Oct 12, 2026 from agency boundaries and USGS PAD-US 4.1 · sources and method

Who manages the land

  • State land (wildlife, trust and natural-resource agencies)4.1%

Share of the unit’s area. Federal agencies plus state wildlife, trust and natural-resource land, as the WikiHunt map classifies it. The rest is private, tribal, local or other land.

Rut: Published deer rut timing for Colorado: Mid-Nov – mid-Dec. Rut dates and sources for Colorado.

Outline of GMU 121 and the units around itGMU 113 · 7.8% publicGMU 115 · 5.5% publicGMU 120 · 10% publicGMU 122 · 3.5% publicGMU 125 · 39% publicGMU 126 · 15% public
GMU 121 in orange; neighbours shaded by public land share (darker = more public). Tap a neighbour to open it.

Units next to GMU 121

Colorado season dates, 2026

Statewide general seasons. Many units have their own dates, quotas or draw-only hunts, so check the unit in the regulations before you go.

SpeciesSeason2026 dates
Deer Archery Deer Sep 2 – Sep 30
Deer Muzzleloader Deer Sep 12 – Sep 20
Deer Combined Rifle Deer Oct 14 – Nov 22
Elk Archery Elk Sep 2 – Sep 30
Elk Muzzleloader Elk Sep 12 – Sep 20
Elk Combined Rifle Elk Oct 14 – Nov 22
Pronghorn Rifle Antelope Oct 3 – Oct 11
Black bear Fall Bear Sep 2 – Nov 30

Full notes on the Colorado page · Colorado regulations.

Questions

How much of GMU 121 is public land?

About 4.2% of GMU 121 (28,201 of 671,458 acres) is federal or state public land in USGS PAD-US 4.1, mostly State land (wildlife, trust and natural-resource agencies). Public land is not always open land: check access and closures before you go.

Who manages the land in GMU 121?

State land (wildlife, trust and natural-resource agencies): 4.1%. The rest is private, tribal, local government or other land.

Which units border GMU 121?

GMU 113, GMU 115, GMU 120, GMU 122, GMU 125 and GMU 126.

Where are the season dates and rules for GMU 121?

Colorado Parks and Wildlife sets them. Start at the Colorado hunting regulations. WikiHunt shows the statewide general seasons on the Colorado page and in the app.

Sources and method

  • Boundary: Colorado Parks and Wildlife, the same layer the WikiHunt map draws.
  • Public land: USGS Protected Areas Database (PAD-US) 4.1, Fee Managers layer (public domain).
  • Method: the unit and PAD-US polygons are simplified to about 100 m and measured on a grid of about 250 cells across the unit, so overlapping records are counted once. Expect about ±1 percentage point.
  • Season dates: WikiHunt’s season table, updated Sep 2, 2026, checked against each state’s published regulations. Dates change; the regulations win.
  • Last updated: Oct 12, 2026. Spotted a mistake? Tell us.