Unit S28 (Vallecito)
Colorado Hunting Guide — Bighorn Sheep
Unit S28 lies in Hinsdale, La Plata and San Juan counties. CPW bounds it by Continental Divide and North Fork Los Pinos River among others. CPW's harvest estimates put bighorn sheep success here as high as 100%. Federal land covers about 67% of it. Check land status on a current map before you plan a route.
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Bighorn Sheep Hunting in Unit S28
Unit S28 lies in Hinsdale, La Plata and San Juan counties. CPW bounds it by Continental Divide and North Fork Los Pinos River among others. CPW's harvest estimates put bighorn sheep success here as high as 100%. Federal land covers about 67% of it. Check land status on a current map before you plan a route.
Where to Find Bighorn Sheep in Unit S28
CPW draws an exact line around unit S28 and says nothing about where the bighorn sheep stand inside it. Every place named below sits inside the unit line. Which of them holds animals in your season is for you to find out. The unit lies in Hinsdale, La Plata and San Juan counties.
The lines of the unit: Continental Divide, North Fork Los Pinos River and Los Pinos River
CPW has unit S28 bounded on the north by Continental Divide; on the east by North Fork Los Pinos River, Los Pinos River, USFS Trail 539 from Divide Lakes and Weminuche Creek; on the south by Hinsdale-Archuleta Co. line, East Creek and Los Pinos River; on the west by Vallecito Reservoir (east shoreline) and Vallecito Creek. Read it as a frame, not as a hint about animals. Its value is practical — those are the features you will navigate by, and the ridges that separate one day's country from another's.
High ground inside the line: Rio Grande Pyramid, Mount Oso and Irving Peak
Named high points inside the unit include Rio Grande Pyramid at 13,803 feet, Mount Oso at 13,634 feet, Irving Peak at 13,197 feet, Mount Nebo at 13,187 feet and Hunchback Mountain at 13,085 feet. Several carry a public-land flag in our data, which makes them the first places to try for a view. Sheep need rock to escape into and will not stand far from it.
Holding ground: Snowslide Canyon, Barebottom Park and Cañon Paso
Below them sit Snowslide Canyon at 10,158 feet, Barebottom Park at 10,061 feet, Cañon Paso at 9,916 feet, South Canyon at 9,868 feet and Hell Canyon at 9,035 feet. These are the folds worth watching, and the ones other hunters walk past on the way to somewhere steeper. Work out which of them you can see from one position before you pick a camp.
The herd this unit belongs to: RBS-20
CPW does not manage bighorn sheep unit by unit. It manages them as data analysis unit RBS-20, and unit S28 is one piece of it. The rest of RBS-20 is unit S15 and unit S16. Read a neighbour in the same herd before you read the state average — the herd, not the unit line, is what the agency is steering.
Unit S28 terrain and land status
Measured from the unit boundary, not from the agency write-up
Named features inside the unit
Glass from: Rio Grande Pyramid (13,803 ft), Mount Oso (13,634 ft), Mount Nebo (13,187 ft), Hunchback Mountain (13,085 ft)
Holding ground: Cave Basin (11,373 ft), Runlett Park (10,691 ft), Rincon La Vaca (10,531 ft)
Every one of these was tested against the unit polygon before it went on the map. They are starting points, not agency recommendations.
How to Hunt Bighorn Sheep in Unit S28
Bighorn Sheep Success Rates
CPW's 2023 harvest estimates put bighorn sheep success in unit S28 at 100% — 2 animals taken by 2 hunters. On a sample that small the percentage moves several points with one animal, so read the hunter count beside it.
These are the agency's own printed figures for this unit, not a modelled estimate and not a state average. They describe one season, so check CPW's current harvest estimates before you read a trend into them.
Bighorn Sheep Draw Odds
| Season | Tags | Applicants | Draw % | Pts Req |
|---|---|---|---|---|
| Rifle — 1st Season ram only (resident) | 1 | 70 | 1.4% | 3 |
| Rifle — 1st Season ram only (nonresident) | 0 | 0 | 0.0% | — |
Data from 2026 draw results. Each row is one residency pool — read the label before the number.
Open in Draw Odds EngineCPW's 2026 draw recap for bighorn sheep in unit S28, by hunt code, with resident and nonresident kept apart because the two draw from different licence pools:
- SMS28O1R — Rifle, 1st Season, Ram Only, resident: 70 applicants for 1 licences, 1.4% drawn, 3 preference points needed
Colorado runs a pure preference-point draw, so the point figure above is the requirement the agency published for that code in that year, not a forecast for the next one. Figures checked against CPW's own statistics pages on 2026-06-09.
Unit Logistics & Expectations
Frequently Asked Questions
Where is Colorado unit S28?
What is the bighorn sheep success rate in unit S28?
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Upgrade to Pro — $49/yrSources & Verification
Every fact on this page is tied to a primary source below. Last fact-checked 2026-10-23.
- Colorado Sheep & Goat Hunting Brochure — Game Management Unit (GMU) Descriptions (pp. 16-17) — Colorado Parks and Wildlife · supports: GMU boundary description, Counties the unit lies in, Data analysis unit (DAU) the unit belongs to · accessed 2026-10-22
- 2023 Colorado Rocky Mountain bighorn sheep Harvest Estimates — Colorado Parks and Wildlife · supports: Percent success for bighorn sheep in unit S28, Hunters and harvest by weapon and season · accessed 2026-10-22
- CPW CPWAdminData feature service — GMU and sheep/goat unit boundaries — Colorado Parks and Wildlife GIS Unit · supports: Mapped extent of the unit, Which named ground falls inside the unit line · accessed 2026-10-22