If there is one thing that can be said with certainty about Barcelona, is that there is no lack of things to see. Many cities it is possible to catch the highlights in an afternoon, and then begin to properly explore what secrets the city has to offer. But Barcelona's secrets are on every corner, and you will do well to see half the amazing sights it has to offer. And even so, with all the really stunning sights to see in this visually incredible city, the Spanish Arc de Triomf on the Passeig de Sant Joan is well worth a look. Before I bought my guide for Barcelona, I wasn't even aware that they had an arc, which I find amazing now having seen it in comparison to some of its more famous cousins. It is somewhat oddly situated in an area of town that other wise feels rather like the outskirts. We came around a corner and suddenly, directly in front of us, stood the impressive and imposing red Arc de Triomf, which, in true Catalan style, wasn't raised for any particular triumph. They just thought they should have one.
Personally, I think this Arc is more visually stunning than the one in Paris. The stone work is beautiful--the bright red of it shines in the Mediterranean light and, to me, seems the very essence of what a city like Barcelona stands for. It's beautifully (and conveniently) situated on a long walk way that even in the off-season was full of people meandering along and kids riding skateboards around its base.
The long rows of palm trees lining the walkway up to Arc make for the perfect entrance to the feeling of the city, and if you are coming up from one of the smaller coastal Spanish towns, I recommend that you start Barcelona at this end of the city. It's a really nice start to the sights, and not far from the ocean.
It's free, and a really stunning piece of workman ship. Great for photos and a place to catch your breath before diving further into the depths of Barcelona and her many sights. Well worth seeing.