Transports are used to carry cargo in Nimbus. They can be used to gather Storm Power, to capture immobilised High Priests, and to collect and cast Spells. The only exception is the Priest himself, who cannot capture another Priest.
Transports are divided into two groups: Air and Ground Transports. Air Transports can move without land or bridges, and can land anywhere, regardless of whether there is anything there or not, but they have a taking off and landing time of a few seconds. Ground Transports, on the other hand, can only move over Islands or Bridges, and if they are standing on a bridge when it is destroyed, they fall into the Duesphere and are destroyed.
Units which carry -
Walking transports are the transports which require land and bridges in order to get from one place to another -- this means that they often take longer than Ariel transports to get from A to B, as they have to travel along a network of bridges. When connecting to geysers, you should bear this in mind, as the shorter the trips the walking transports need to make, the faster you will get money.
Another disadvantage of using bridges for transport is the fact that a bridge may break beneath them or ahead of them, causing them to fall down -- Golems are stupid, and will walk right off a bridge even if it is broken; other walking transports will stop at the end, but may still fall down if that bridge breaks beneath them. This can foil attempts to return captured enemy priests to your altar/base.
All of the walking transports are vulnerable to flying attackers such as Man 'o Wars and Dust Devils, but they are not targeted by Whirligigs. It is however worth keeping in mind that wind's Sail Skaters can be be targeted only by Dust Devils if moving because they are too fast for the Man 'o Wars.
Golems are the only walking transports which can move in diagonal directions -- the others can only move up, down, left and right.