Transportation is inadequate. Most roads are little more than tracks, although Funafuti has about 19.5 km (12.1 mi) of coral-impacted roads for use by the island's few cars and trucks. Funafuti and Nukufetau are the only seaports, used chiefly by freighters in the copra trade. Ships drawing up to 9 m (30 ft) can dock in Funafuti harbor at a deepwater wharf completed in 1980. In 2002, Tuvalu had a merchant fleet of 5 ships totaling 31,021 GRT. All the islands are served by Tuvalu's one inter-island ferry. Funafuti has one lone airport, a grass strip that cannot be used for jet aircraft.