Add global custom content areas for your WordPress website. Add to functions.php

global_custom_content

add_action('admin_menu', 'add_gcf_interface');

function add_gcf_interface() {
  add_options_page('Opening hours', 'Opening hours', '8', 'functions', 'editglobalcustomfields');
}

function editglobalcustomfields() {
	?>
	<div class='wrap'>
	<h2>Opening hours</h2>
	<form method="post" action="options.php">
	<?php wp_nonce_field('update-options') ?>

	<p><strong>Enter content here (HTML included)</strong><br />
	<textarea name="open_hours" cols="100%" rows="7"><?php echo htmlentities(get_option('open_hours')); ?></textarea></p>

	<p><input type="submit" name="Submit" value="Update Options" /></p>

	<input type="hidden" name="action" value="update" />
	<input type="hidden" name="page_options" value="open_hours" />

	</form>
	</div>
	<?php
}

// add below to template where required
<?php echo get_option('open_hours'); ?>