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AhaBulb: Stuff Everyone Should Know · ahabulb.com/boat-anchor-light-all-round-white

A boat under 50 meters anchored at night may show what single light?

One all-round white light where it can best be seen.

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  1. A flashing red light
  2. Green and red sidelights
  3. An all-round white light ✔

Why: Inland Rule 30 lets a vessel under 50 meters at anchor show one all-round white light where it can best be seen. That white light, visible from every direction, tells others you're anchored.

Huh, didn't know that: In a Coast Guard designated special anchorage area, boats under 20 meters don't need an anchor light.

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What has a bed but never sleeps? A river.
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References

Answer: An all-round white light. Inland Rule 30 lets a vessel under 50 meters at anchor show one all-round white light where it can best be seen. That white light, visible from every direction, tells others you're anchored.

  1. 33 CFR 83.30 Vessels anchored, aground and moored barges, Inland Rule 30 (eCFR) www.ecfr.gov/current/title-33/section-83.30
    A vessel of less than 50 meters in length may exhibit an all-round white light where it can best be seen
    Checked 2026-10-08.
  2. 33 CFR 83.30 Vessels anchored, aground and moored barges, Inland Rule 30 (eCFR) www.ecfr.gov/current/title-33/section-83.30
    A vessel of less than 20 meters in length, when at anchor in a special anchorage area designated by the Coast Guard
    Checked 2026-10-08.

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Boating & WaterWhen must recreational boats show their navigation lights?Boating & WaterAt night you see only another boat's white sternlight, no red or green. What situation is this?Boating & WaterA sailboat moving under sail alone at night shows which lights?

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