<link href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css"> <script src="//maxcdn.bootstrapcdn.com/bootstrap/3.3.0/js/bootstrap.min.js"></script> <script src="//code.jquery.com/jquery-1.11.1.min.js"></script> <!------ Include the above in your HEAD tag ----------> <div class="container"> <div class="row"> <h2>Photo Gallery Preview with large and small images align</h2> </div> <div class="row img-thumbnails"> <div class="col-md-6"> <a href="#"> <img src="http://lorempixel.com/600/600/nature/1/" class="img-thumbnail"> </a> </div> <div class="col-md-6"> <a href="#"> <img src="http://lorempixel.com/600/600/nature/2/" class="img-thumbnail"> </a> </div> <div class="col-md-4"> <a href="#"> <img src="http://lorempixel.com/600/600/nature/3/" class="img-thumbnail"> </a> </div> <div class="col-md-4"> <a href="#"> <img src="http://lorempixel.com/600/600/nature/4/" class="img-thumbnail"> </a> </div> <div class="col-md-4"> <a href="#"> <img src="http://lorempixel.com/600/600/nature/5/" class="img-thumbnail"> </a> </div> </div> </div>

.img-thumbnails .img-thumbnail { margin-top: 15px; }