Discover Padua Botanical Garden

The original design is a hortus sphaericus: a circle roughly 84 metres across, enclosed by a wall, quartered by two paths crossing at right angles. The geometry is not decorative -- it was a filing system, dividing the collection into orderly beds a student could learn by walking.

Later centuries added gates, fountains and glasshouses around the circle without disturbing it, which is the main reason the 1545 layout survives intact enough to read on the ground.

The Garden of Biodiversity of 2014 is deliberately the opposite: a long glass and steel structure holding five climate zones, sited outside the historic wall so that the old garden keeps its own edges. The contrast between the two is unusually well handled.