Chart No. 1 · Q 23
Pillar buoy
Buoys & beacons
A broad base with a tall narrow superstructure — the workhorse shape for cardinal and sea buoys.
What it means
A wide base carrying a tall, narrow tower is a pillar buoy — used where a mark must be seen from far off, such as cardinal marks and landfall buoys.
Why it matters
Because a pillar's shape is neutral, its meaning comes entirely from color, topmark, and light — read those, not the outline.