Port projects with Navarra. Ten years later, the people of Fuenterrabía ed that the Cortes of Navarra study, in the interest of both the town and the viceroyalty, the possibility of canalizing the Bidasoa River to facilitate Navarra’s foreign trade. Navarra responded by depositing one thousand gold ducats to aid the works, which were auctioned twice without practical results.
Ciriquian notes that Tolosa and San Sebastián protested, since this canalization would have harmed the transit rights of the former and the port interests of the latter. Nevertheless, negotiations Fuenterrabía and Navarra continued. The Navarrese viceroy visited the river and entrusted the drafting of the canalization project to Master Gil of Gallur. Fuenterrabía left in Pamplona, as a guarantee of its commitments, the base of a cross weighing more than 11 kg that belonged to the town.
The project did not come to fruition, although it was renewed in one form or another in 1569, 1597, and 1638 without success, and the issue continued to be raised until the 19th century.