This code snippet customizes the map zooming and bounds. Add this code to the functions.php file in the theme directory.

um_user_locations_map_args_customize_03.php

<?php

/**
 * Restricting Map Bounds and Zoom.
 */
add_action( 'wp_footer', function () {
	?><script type="text/javascript">

		function um_user_locations_customize_03 ( args, hash, directory ) {
			args.center = {
				lat: 50,
				lng: 15
			},
			args.restriction = {
				latLngBounds: {
					north: 71.4,
					south: 29.4,
					east: 40,
					west: -10.5
				}
			};
			args.zoom = 5;
			args.minZoom = 4;
			args.maxZoom = 9;
			return args;
		}

		// customize the map in the member directory.
		wp.hooks.addFilter( 'um_user_locations_map_args_init', 'um_user_locations', um_user_locations_customize_03 );

		// customize the map in profiles.
		wp.hooks.addFilter( 'um_user_locations_map_field_args_init', 'um_user_locations', um_user_locations_customize_03 );
	</script><?php
}, 20 );

This gist is a part of the article User Locations - Hooks.
Related article - Disabling Pan and Zoom.

You can add this code to the functions.php file in the active theme directory. Skip the opening <?php tag.