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    1. Home
    2. Fifth wheel trailers
    3. Forest River
    4. RiverStone
    Forest River RiverStone 421FK exterior

    Forest River RiverStone 421FK

    Rear bedroom, desk, dual vanity, bar seating

    • Rear bedroom
    • Front kitchen
    • Desk
    • Dual vanity
    • Bar seating
    Browse inventory (48)
    Forest River RiverStone 421FK floor plan

    Find a Forest River RiverStone 421FK

    See it in person or find a great deal nationwide.
    Browse inventory (48)

    Similar floor plans

    Fifth wheel trailers that share features with the RiverStone 421FK, like kitchen island, east west bed and fireplace.

    Alliance RV Paradigm 310RL exterior

    Alliance RV Paradigm 310RL

    Front bedroom, rear living area

    MSRP$115,822

    210 units available

    Alliance RV Paradigm 310RL floor plan
    Max weight

    16,000 lbs

    Length

    34 ft 11 in

    Sleeps

    4

    Forest River Cedar Creek Experience 2925RL exterior

    Forest River Cedar Creek Experience 2925RL

    Farmhouse sink

    MSRP$102,704

    5 units available

    Forest River Cedar Creek Experience 2925RL floor plan
    Max weight

    14,343 lbs

    Length

    34 ft 11 in

    Sleeps

    3

    East to West Ahara 325RL exterior

    East to West Ahara 325RL

    Front bedroom, rear living area, walk-thru bath

    MSRP$108,460

    10 units available

    East to West Ahara 325RL floor plan
    Max weight

    15,500 lbs

    Length

    34 ft 9 in

    Sleeps

    4

    Heartland Corterra CT 3.0 exterior

    Heartland Corterra CT 3.0

    Front bedroom, rear living area, walk-thru bath

    MSRP$90,742

    6 units available

    Heartland Corterra CT 3.0 floor plan

    RV Envy's expert take

    We like: Ample bedroom storage, Modern lighting

    Consider: Only one nightstand

    Max weight

    14,000 lbs

    Length

    34 ft 9 in

    Sleeps

    4

    East to West Blackthorn 3100RL exterior

    East to West Blackthorn 3100RL

    MSRPTBD

    4 units available

    East to West Blackthorn 3100RL floor plan

    RV Envy's expert take

    Consider: Very little bedroom storage, No nightstands, Shallow pantry

    Max weight

    14,125 lbs

    Length

    35 ft 4 in

    Sleeps

    6

    East to West Tandara 320RL exterior

    East to West Tandara 320RL

    MSRP$66,073

    5 units available

    East to West Tandara 320RL floor plan
    Max weight

    14,125 lbs

    Length

    35 ft 4 in

    Sleeps

    6

    CrossRoads Cruiser Aire CR31SI exterior

    CrossRoads Cruiser Aire CR31SI

    Rear living area, walk-thru bath, booth dinette

    MSRP$79,505

    4 units available

    CrossRoads Cruiser Aire CR31SI floor plan
    Max weight

    11,910 lbs

    Length

    35 ft 1 in

    Sleeps

    6

    Keystone Alpine 3011CK exterior

    Keystone Alpine 3011CK

    Front bedroom, rear living area, walk-thru bath

    MSRP$110,453

    6 units available

    Keystone Alpine 3011CK floor plan
    Max weight

    15,000 lbs

    Length

    34 ft 11 in

    Sleeps

    4

    Other RiverStone floor plans

    Forest River RiverStone 37FLTH

    MSRPTBD

    2 units available

    Forest River RiverStone 37FLTH floor plan
    Max weight

    21,000 lbs

    Length

    42 ft 2 in

    Sleeps

    6

    Forest River RiverStone 37IK

    MSRPTBD
    Forest River RiverStone 37IK floor plan
    Max weight

    19,023 lbs

    Length

    40 ft 3 in

    Sleeps

    5

    Forest River RiverStone 37MRE

    MSRPTBD
    Forest River RiverStone 37MRE floor plan
    Max weight

    16,595 lbs

    Length

    41 ft 3 in

    Sleeps

    6

    Forest River RiverStone 37REL

    MSRPTBD
    Forest River RiverStone 37REL floor plan
    Max weight

    19,055 lbs

    Length

    41 ft 5 in

    Sleeps

    6

    Forest River RiverStone 383MB

    MSRPTBD

    1 unit available

    Forest River RiverStone 383MB floor plan
    Max weight

    16,262 lbs

    Length

    41 ft 6 in

    Sleeps

    4

    Forest River RiverStone 38BMB

    MSRPTBD

    4 units available

    Forest River RiverStone 38BMB floor plan
    Max weight

    19,250 lbs

    Length

    41 ft 6 in

    Sleeps

    4

    Forest River RiverStone 391FSK

    Front kitchen with bar seating, desk

    MSRPTBD

    8 units available

    Forest River RiverStone 391FSK floor plan

    RV Envy's expert take

    We like: Large front kitchen, Barstyle seating, Kitchen sink looks out window, Ample counter space, Division of space, Built in work desk, Two entry doors, Bathroom accessible with slides closed

    Consider: No dinette, Bedroom is tight, Exterior door opens into bedroom, Small mid-bathroom

    Max weight

    18,555 lbs

    Length

    42 ft 8 in

    Sleeps

    5

    Forest River RiverStone 39FK

    MSRPTBD

    6 units available

    Forest River RiverStone 39FK floor plan
    Max weight

    18,665 lbs

    Length

    42 ft 2 in

    Sleeps

    5

    Forest River RiverStone 39FL

    MSRPTBD
    Forest River RiverStone 39FL floor plan
    Max weight

    19,065 lbs

    Length

    41 ft 9 in

    Sleeps

    8

    Forest River RiverStone 39MO

    MSRPTBD

    2 units available

    Forest River RiverStone 39MO floor plan
    Max weight

    18,989 lbs

    Length

    41 ft 8 in

    Sleeps

    5

    View all RiverStone floor plans →
    Forest River RiverStone 421FK overview
    • Rear bedroom
    • Front kitchen
    • Desk
    • Dual vanity
    • Bar seating
    Forest River RiverStone 421FK exterior

    Key facts

    Length
    45 ft
    Max weight
    24,000 lbs
    Sleeps
    4

    Specs

    Dimensions

    Length
    45 ft
    Height
    13 ft 4 in
    Width
    8 ft 6 in
    Slideouts
    5
    Axles

    Key facts

    Length
    45 ft
    Max weight
    24,000 lbs
    Sleeps
    4

    AI summary

    The front kitchen layout is the 421FK's signature move — you get a full-size French door refrigerator with ice maker, Fisher & Paykel dishwasher, four-burner range with convection microwave, Calcutta solid surface countertops, and a kitchen island with bar seating that would look at home in a real house. The rear King bed suite adds a dual vanity, 40" smart TV, and a dedicated desk slide, so there's a genuine separation between living and sleeping spaces. Residential touches run deep: Truma on-demand hot water, Splendide stackable washer/dryer, 5,200 BTU fireplace, hardwood dovetail drawers with soft-close everything, and two 15,000 BTU heat pump A/Cs keeping both ends comfortable. The automatic 6-point hydraulic leveling and LCI Road Armour suspension make setup and towing far less of a production than you'd expect from a rig this well-appointed.

    2

    Tanks & capacities

    Fresh water
    79 gal
    Gray water
    120 gal
    Black water
    40 gal

    Weight & towing

    Dry weight
    18,780 lbs
    GVWR
    24,000 lbs
    Hitch weight
    3,270 lbs
    1 ton truck required
    New Ford F-350, RAM 3500, Sierra 3500, or bigger

    Based on overall weight and weight directly on tow vehicle's hitch and a new model tow vehicle. Please consult with a professional.

    Accommodations

    Sleeps
    4
    Download brochure

    Available years

    2027202620252024
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    Forest River RiverStone 421FK floor plan