Magento - Proceed to Checkout button location in theme

I am looking to track down the file (and it's location) that generates the "Proceed to Checkout" button in the Magento cart.

Try adding a product to the cart, and then proceeding to the cart. The "Proceed to Checkout" button is on the right hand side of the cart.

I am using a hacked-about variation of the blank theme, if that makes any difference.

Thanks in advance for your help.

The code that produces the Proceed to Checkout link is in templates/checkout/onepage/link.phtml

By default the block for it is in checkout.xml;

            <block type="core/text_list" name="checkout.cart.methods" as="methods" translate="label">
                <label>Payment Methods After Checkout Button</label>
                <block type="checkout/onepage_link" name="checkout.cart.methods.onepage" template="checkout/onepage/link.phtml"/>
                <block type="checkout/multishipping_link" name="checkout.cart.methods.multishipping" template="checkout/multishipping/link.phtml"/>
            </block>