Using front matter to link to outside URLs

It’s very likely (surprise!) that I’m not understanding what’s happening behind the curtain. I’m able to loop through my posts just fine. The front matter populates the content of each project. Here’s one for plan-it:

layout: post
title: Plan-It
description: Android monthly planner, In-app purchases
client: SixFive Agency
role: Design, development
launchDate: June 2016
thumbnail: planit.jpg
mainImage: planit.jpg
date: 2016-06-01 20:17:17 -0700
categories: portfolio
You’ll find this post in your `_posts` directory. 

In my portfolio.html _includes file, I’m looping through them like this:

{% for items in site.categories.portfolio %}

            <a href="{{items.url}}" data-largesrc="images/portfolio/{{items.mainImage}}" data-title="{{items.title}}" data-description="{{items.description}}
            <span class='client'><strong>Client: </strong>{{items.client}}</span>
            <span class='role'><strong>Role: </strong>{{items.role}}</span>
            <span class='year'><strong>Launched: </strong>{{items:launchDate}}</span>">   
                <img src="images/portfolio/thumbs/{{items.thumbnail}}" alt="img09" />

    {% endfor %} 


I’d like to generate a button at the end of that loop that pulls in the url from my front matter. But whenever I try this, the url ends up being something like ‘http://localhost:4000/portfolio/2016/06/01/plan-it.html


Thanks, Bill

don’t use url as a front matter custom variable - name it something else like portfolio-url.

I think it is clashing with jekylls built in url for that post.