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Flagg Park
Flagg Park

Flagg Park

The Flagg Park trailhead in Lafayette provides access to the Coal Creek Trail and Rock Creek Trail and is part of the Two Creeks Open Space.


  • Coal Creek Trail
    14 miles – Easy
    Hiking Allowed Dogs Allowed Bikes Allowed E-bikes Allowed Horses Allowed
  • Rock Creek Trail
    14 miles – Easy
    Hiking Allowed Dogs Allowed Bikes Allowed E-bikes Allowed Horses Allowed

Trails Connections

Rules & Regulations

Bikes On Designated Trails Only
Pets On Leash
No Drones
No Hunting/Firearms
No Camping

All Parks & Open Space Rules & Regulations

Trailhead Amenities

18 car parking spots
1 ADA van accessible parking spot
2 horse trailer parking spots

See Photos

Keep in Mind

  • Equestrians are not allowed on a majority of the Coal Creek Trail due to city of Lafayette and Louisville regulations.
  • Regional trails and regional trail connectors are open to commuters 24 hours per day. Trailheads close at sunset and parking is not allowed between sunset and sunrise.


  • American beaver
  • Black-tailed prairie dog
  • Common muskrat
  • Coyote
  • Eastern cottontail
  • Mice
  • Raccoon
  • Red fox
  • Striped skunk
  • Voles
  • Whitetail deer

Reptiles & Amphibians

  • Woodhouse toad
  • Bull snake


  • Black damsel bug
  • Ebony jewelwing
  • Russet Skipperling


  • American kestrel
  • Brewer’s blackbird
  • Brown-headed cowbird
  • Cedar wax wing
  • Chipping sparrow
  • Ferruginous hawk
  • House finch
  • Merlin
  • Red-tailed hawk
  • Red-winged blackbird
  • Say’s phoebe
  • Turkey vulture
  • Western meadowlark
  • Yellow-rumped warbler


  • Creek chub
  • Fathead minnows
  • Green sunfish
  • Longnose dace
  • White sucker

Trees & Shrubs

  • Box elder (Negundo aceroides)
  • Coyote willow (Salix exigua)
  • Narrowleaf cottonwood (Populus angustifolia)
  • Peachleaf willow (Salix amygdaloides)
  • Plains cottonwood (Populus deltoides)

Purple & Blue Wildflowers

  • Tansy aster (Machaeranthera tanacetifolia)

Red & Orange Wildflowers

  • Scarlet globemallow (Sphaeralcea coccinea)
  • Showy milkweed (Asclepias speciose)

White Wildflowers

  • Common yarrow (Achillea millefolium)
  • Thistle poppy (Argemone polyanthemos)
  • Yucca (Yucca glauca)

Yellow Wildflowers

  • Broom snakeweed (Gutierrezia sarothrae)
  • Hairy false goldenaster (Heterotheca villosa)
  • Prickly pear (Opuntia polyacantha)
  • Rubber rabbitbrush (Chrysothamnus nauseosus)

Flagg Park lies within the Boulder-Weld Coal Field and coal mining activity was very prevalent in the area during the late 1800s into the early/mid 1900s.

Flagg Park is one of ten open space properties along Coal Creek owned by the City of Lafayette and Boulder County. It was purchased to preserve wildlife habitat, provide a buffer between cities, and maintain the rural character and agricultural lifestyle of the area.

Developing this property into a community park began in 1979 with the process of reclamation from a landfill. Reclamation continued with drill seeding in 1980 to bring the historic shortgrass prairie species back to Flagg Park.

Contact Us

Parks & Open Space

8 a.m. to 4:30 p.m.

Office Location

5201 St. Vrain Road
Longmont, CO 80503
Map and Directions
Office Hours: 8 a.m. to 4:30 p.m.
Friday by phone, email, or appointment only.

Parks are open sunrise to sunset