with Roraima is Amazonas, through the BR-174, which connects the municipalities in the South to the municipalities in the North of the state, and is also responsible for connecting Brazil to Venezuela. The BR-174 is long and crosses the territory of the state from south to north, crossing the Branco River at the height of Caracaraí through the Caracaraí Bridge. There is also the BR-210, also called Perimetral Norte, a project originating in the mid-twentieth century, from the Federal Government, which had been carried out only partially and which, in principle, would link the state to Pará, Amapá and the municipality of São Gabriel da Cachoeira (in Amazonas). This highway is long and crosses the state in an east–west direction. Another highway in Roraima that crosses Brazil is the BR-401, connecting the state with Guyana. It starts in Boa Vista and crosses the Branco River through the Macuxis' Bridge, entering the Guyanese territory. Other federal highways are BR-431, BR-432 and BR-433. Federal roads in Roraima add up to . There are state highways as well, including the RR-205 (which connects the capital to the headquarters of Alto Alegre) and the RR-203 (connecting the headquarters and districts of Amajari to the BR-174), both of which are fully paved, signposted, and with good traffic conditions. Other important highways are the RR-325 and the RR-319, which cut through important agricultural areas and colonies of rural settlements. State highways add up to just over in length and are largely in conditions of improper use. Waterways River transport is also notable in the state, as well as in other states in the Amazon rainforest. However, river navigation is limited to the Branco River. Transportation on the Branco River is heavily used for the economy, but with little passenger movement to inland cities. Regular navigation on this river occurs only in the mouth section (Negro River/Caracaraí), about long. In this segment, the Branco River has a maximum draft of 5 metres in the period of floods and a minimum of 0.7 metres in the period of drought. Roraima is at a disadvantage in relation to the other Amazonian states in terms of waterway system. As it is the only one in which all its notorious rivers have their source in their own territory – the state's hydrographic system is 100% Roraiman –, it is bound to have few river outlets. In fact, Roraima has only one