There might be some WordPress plugins out there that could be used to add Google map to posts and pages. Still I didn’t find it necessary to install one when creating it is fun and easy.
Adding the final plugin to a post/page will be done using shortcode.
First of all you must create the plugin directory in wp-content/plugins/plugin_name.
Add two files here, the first an empty index.php and the second plugin_name.php
In order to be able to activate this plugin some basic details need to be added at the beginning:
/**
* Plugin Name: Custom Google Maps
* Plugin URI: http://catalinmunteanu.com
* Description: Create Google Map element using a location query
* Version: 1.0.0
* Author: Catalin Munteanu
* Author URI: http://catalinmunteanu.com
*/
Then we must create a function that will process this plugin’s shortcode:
function google_map_print($attrs, $content=null) {
   $item = shortcode_atts(
       array(
           'location' => null
       ),
       $attrs,
       'google-map'
   );
   $result = '<div>';
       $result .= '<iframe
           width="100%"
           height="250"
           scrolling="no" marginheight="0" marginwidth="0"
           frameborder="0" style="border:0"
           src="https://maps.google.com/maps?f=q&hl=en&geocode=&q='.$item['location'].'&aq=t&ie=UTF8&hq=&t=m&z=17&output=embed">
           </iframe>';
   $result .= '</div>';
   return $result;
}
add_shortcode('google-map', 'google_map_print');
That’s all. After you activate the plugin you can add it in your posts and pages using the shortcode:
[google-map location="Bucharest"]
Result:
[custom-google-map location=”Bucharest”]