The top-bar hive: one long house

A top-bar hive is not a stack: one long trough-shaped body holding twenty to thirty bars laid side by side instead of boxes stacked on top of each other.

Bees are given a wedge on the underside of each bar and build their own comb downward from it, in whatever shape they choose, and a movable board lets you shrink or grow the usable space as the colony does. The design's sloped inner walls keep bees from gluing comb to the sides instead of hanging it cleanly from the bar above.

Nothing about a top-bar hive is ever lifted as a full box. You lift one bar of comb at a time, whatever weight the whole hive is carrying between its bars.