<Tr> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> <Table> <Tr> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr> </Table> </Td> <Td> </Td> <Td_colspan="2"> High rail bridge </Td> </Tr> <Table> <Tr> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr>

Where does the river nene start and finish