Skiff

A skiff is a small rowing boat that can hold up to eight persons. Skiffs are made to travel over shallow waters where bigger ships can't pass, and are also able to enter moderately deep waters in order to dock with said ships. However, deep seas are very dangerous for skiffs, and they tend to sink quickly under such conditions. Every shipwright has skiffs for sale, and if the adventurer actually buys a frigate, a skiff is already included in the price of the ship.

Skiffs appeared for the first time in Ultima V, where the Avatar could either purchase one from a shipwright, or have it included with a frigate. They were necessary to reach the shallow waters that the larger frigates couldn't.

In Ultima VI, skiffs gained the ability travel over all water surfaces, and no could longer dock with frigates. However, a strong companion now was able to carry the skiff to also safely pass underwater rivers.

After that time, skiffs no longer were usable, and the ones encountered were either static (as in Ultima VIII) or part of a ferry system (as seen in Ultima IX).

The Ultima 6 Project
In the Ultima 6 Project, the various shipwrights in Britania tell the Avatar, that due to the current war situation they do not have any skiffs to offer. Dupre reacts with relief to these news, having feared the Avatar would force him to carry the skiff. This banter is a reference to the original Ultima VI, where it indeed was the best idea to let Dupre as the strongest character carry a skiff in the inventory.