This hook  lets you add the custom content in trip overview content.

Source

File : /inc/template-functions.php

Example :

function prefix_wp_travel_trip_details() {
    esc_html_e( 'This is the content added using this hook', 'text-domain' );
}
add_action( 'wp_travel_trip_details', 'prefix_wp_travel_trip_details'  );