gistfile1.php

            'home' => array(
                'type' => 'literal',
                'options' => array(
                    'route' => '/project[/:project_id]/project-item',
                    'defaults' => array(
                        'controller' => 'Item\Controller\Index',
                        'action' => 'index',
                    ),
                    'constraints' => array(
                     'project_id' => '[0-9]+'
                    )
                    
                ), 
                'may_terminate' => true,
                'child_routes' => array(
                        'details' => array(
                        'type' => 'literal',
                        'options' => array(
                            'route' => '/details',
                            'defaults' => array(
                            'action' => 'details'
                            ),
                            'constraints' => array(
                                 'project_id' => '[0-9]+'
                                )
                        ),
                )
                )
            )