HTML ul elements aren't centering properly

still very new to HTML and such so apologies if this is a very simple issue...

I have a problem in formatting, I've tried centring the navigation elements of my document but they don't seem to do so properly.

Here's an image of the issue in the browser - https://i.sstatic.net/Y3mqp.png

Here's my HTML. (with some cake ipsum in there to boot)

<!DOCTYPE html>
<html>

<head>
    <meta charset="UTF-8">
    <title>About Me Example Page:</title>
    <link href="../css/aboutcss.css" type="text/css" rel="stylesheet" />        
</head>

    <body>

        <div id="wrapper">  

            <h1><img src="../images/about/aboutlogo.png" alt="About Me" style="height:100px;"></h1>

            <nav>   

                <ul>
                <hr align="center"/>
                    <li><a href="../index.html">Home</a></li>
                    <li><a href="../portfolio/index.html">Portfolio</a></li>
                    <li><a href="../contact/index.html">Contact</a></li>
                    <li><a href="../blog/index.html">Blog</a></li>
                <hr />
                </ul>

            </nav>  

            <img src="../images/about/aboutmephoto.jpg" id="me">

            <p>Hello there!</p>

            <p>Liquorice powder liquorice dragée macaroon. Dessert oat cake pastry cheesecake wypas brownie icing. Marzipan sweet dragée icing candy wafer tart macaroon pie. Halvah liquorice pie carrot cake pie. </p>

            <p>Liquorice powder liquorice dragée macaroon. Dessert oat cake pastry cheesecake wypas brownie icing. Marzipan sweet dragée icing candy wafer tart macaroon pie. Halvah liquorice pie carrot cake pie. </p>

                <hr align="center" width="50%" />

            <p>Liquorice powder liquorice dragée macaroon. Dessert oat cake pastry cheesecake wypas brownie icing. Marzipan sweet dragée icing candy wafer tart macaroon pie. Halvah liquorice pie carrot cake pie. </p>

            <p>Liquorice powder liquorice dragée macaroon. Dessert oat cake pastry cheesecake wypas brownie icing. Marzipan sweet dragée icing candy wafer tart macaroon pie. Halvah liquorice pie carrot cake pie. </p>        

            <footer>
            &copy; Me 2012 
            </footer>

        </div>

        </body>
</html>

And the CSS for the same page:

    body {
background-color: #3D3D3D;
    }

    p, a, footer {
font-family: 'Open Sans', Sans Serif;
    }

    h1 * {
height: 125px;
display: block;
margin: 0 auto; 
}

    p {
color:#E2E2E2;  
font-size: 13px;
margin-left: auto;
margin-right: auto;
padding-left: 10px;
padding-right: 10px;
}

    footer {
font-size: 9px;
padding-bottom: 8px;
text-align: center; 
color:#E2E2E2;  
}

    nav {
text-align:center;  
}

    nav li {
display: inline;
    }

    nav a {
display: inline-block;  
text-decoration: none;
color: #E2E2E2;
font-size: 17px;
font-variant: small-caps;
font-weight: bold;
padding:0;
margin-left: 3em;
margin-right: 3em;
}   

    a:visited {
color:#E2E2E2;  
}

    #wrapper {
max-width: 1200px;
width: 90%;
background-color: #1A1A1A;  
margin-left: auto;
margin-right: auto; 
border-style: solid;
border-width: 2px;
border-color: black;
    }

    #me {
margin: 25px;
border-style: solid;
border-width: 5px;
border-color: #656565;
height:300px;   
float:right;
}

Thanks in advance for the help!

Solution

Remove: hr of ul.

And put:

nav ul {
    border-width: 2px 0px 2px 0px ;
    border-style: solid ;
    border-color: #FFFFFF;
    padding: 5px 0px 5px 0px;
}

Regards.