user16065: I have studied the London opening system on lichess.org. What really clicked with me are the systems two main ideas: (1) develop a defensive structure which (2) allows you to crash black's kingside castle by pushing pawns with rooks behind them (and very often crush your opponent).
What you have is plan A, which is to crash black's king side, and if black doesn't castle you return to plan B, which is to improvise from a very strong defensive posture. The main point is that you have plan A with a very specific way to win in mind.
I am /not/ asking about opening principles. I am asking about the specific ideas of the Ruy Lopez. I understand how it gets your pieces out fast, is aggressive, and allows for a fast castle. But what approach or strategy does the Ruy Lopez aim for? 
In my own games, the best idea I have is to position my rook in the center file (because I can castle quickly) and try to open up the center and use a discovered attack on the king or queen by exposing my rook. But is this 'classical'? 

user-1: What you said about how fast White castles and can open center (and give a check) are the tactical resources that white uses to achieve their strategic goals. Of course in modern day every minimally educated player knows the tenets of opening stage and will not allow a mate in 15 by letting White open up the center and bring all minor pieces and take on f7 and mate!
So, what is the longterm strategy? Well, I am not an expert in 1.e4 opening generally, but, can tell from many games I have seen in Ruy Lopez that white is aiming to 
1) Restrict Blacks's choices in the opening. Notice how Black can't really dictate anything in the opening, Black's pieces have basically one square to choose from. White later plays h3 to take g4 away from the bishop on c8.
2) Obtain a mobile center (possibility of being able to push pawns (d4) to open the center) -- think pawns on c3 and d3 and e4 -- this is in contrast with 1.d4 openings where later the center locks with white's pawn ending in d5 and the game "slows down".
3) While preventing Black from freeing their position, white exports another knight to the king side, maneuvers the bishop from b5 to b3, or c2, and gets ready to assault an attack on the king side by occupying f5/h5 with a knight, pushing d4 to open the center and activating the bishops, and even maybe bringing rooks to g file or even the third rank. I must admit I was horrified by Ruy Lopez personally, and never could equalize as Black. (Now I exclusively play Sicilian against 1.e4)
Of course this is a particular line I have in my mind, and many variations are out there with maybe drastically different strategies.
Added: See answers to Why is the Ruy Lopez such a common opening? (I am surprised how right I was!)

user13012: The answer to this is way beyond my pay grade, but I may be able to say something that prepares you for a better answer.
You are not only comparing two very different opening systems (London System and Ruy Lopez), but you are comparing two different ideas of what an opening system is. The London system was once described by GM Julian Hodgson as the "businessman's opening", ideal for those with little time for study, because once you have played d4 and Bf4 there is not much choice for the other pieces. It can be said without gross exaggeration that the London system can be learned in five minutes.
The Ruy Lopez is much more vague and much more ambitious. The vagueness is why no short answer is possible. The goal is to increase Whites mobility and control of space and to retain the option of where to strike. There are some standard manoeuvers such as c3 and d4,0-0 and Re1,Nb1-d2-f1-e/g3, a4, and others, but Black can often play a big role in deciding the sort of game it will be. He can go for complicated counterattack with the Schliemann, the Open, or the Marshall. He can play more safely, with Steinitz/Steinitz Deferred or more classical approaches like the Chigorin, Keres, Breyer.. In fact one reason NOT to play the Lopez is all of the work required to prepare for everything that might happen. Mastering the Lopez is a lifetimes work.

16065: <p>I have studied the London opening system on lichess.org. What really clicked with me are the systems two main ideas: (1) develop a defensive structure which (2) allows you to crash black's kingside castle by pushing pawns with rooks behind them (and very often crush your opponent).</p>

<p>What you have is plan A, which is to crash black's king side, and if black doesn't castle you return to plan B, which is to improvise from a very strong defensive posture. The main point is that you have plan A with a very specific way to win in mind.</p>

<p>I am /not/ asking about opening principles. I am asking about the specific ideas of the Ruy Lopez. I understand how it gets your pieces out fast, is aggressive, and allows for a fast castle. But what approach or strategy does the Ruy Lopez aim for? </p>

<p>In my own games, the best idea I have is to position my rook in the center file (because I can castle quickly) and try to open up the center and use a discovered attack on the king or queen by exposing my rook. But is this 'classical'? </p>
 -1: <p>What you said about how fast White castles and can open center (and give a check) are the tactical resources that white uses to achieve their strategic goals. Of course in modern day every minimally educated player knows the tenets of opening stage and will not allow a mate in 15 by letting White open up the center and bring all minor pieces and take on f7 and mate!</p>

<p>So, what is the longterm strategy? Well, I am not an expert in 1.e4 opening generally, but, can tell from many games I have seen in Ruy Lopez that white is aiming to 
1) Restrict Blacks's choices in the opening. Notice how Black can't really dictate anything in the opening, Black's pieces have basically one square to choose from. White later plays h3 to take g4 away from the bishop on c8.</p>

<p>2) Obtain a mobile center (possibility of being able to push pawns (d4) to open the center) -- think pawns on c3 and d3 and e4 -- this is in contrast with 1.d4 openings where later the center locks with white's pawn ending in d5 and the game "slows down".</p>

<p>3) While preventing Black from freeing their position, white exports another knight to the king side, maneuvers the bishop from b5 to b3, or c2, and gets ready to assault an attack on the king side by occupying f5/h5 with a knight, pushing d4 to open the center and activating the bishops, and even maybe bringing rooks to g file or even the third rank. I must admit I was horrified by Ruy Lopez personally, and never could equalize as Black. (Now I exclusively play Sicilian against 1.e4)</p>

<p>Of course this is a particular line I have in my mind, and many variations are out there with maybe drastically different strategies.</p>

<p>Added: See answers to <a href="https://chess.stackexchange.com/questions/226/why-is-the-ruy-lopez-such-a-common-opening">Why is the Ruy Lopez such a common opening?</a> (I am surprised how right I was!)</p>
 13012: <p>The answer to this is way beyond my pay grade, but I may be able to say something that prepares you for a better answer.</p>

<p>You are not only comparing two very different opening systems (London System and Ruy Lopez), but you are comparing two different ideas of what an opening system is. The London system was once described by GM Julian Hodgson as the "businessman's opening", ideal for those with little time for study, because once you have played d4 and Bf4 there is not much choice for the other pieces. It can be said without gross exaggeration that the London system can be learned in five minutes.</p>

<p>The Ruy Lopez is much more vague and much more ambitious. The vagueness is why no short answer is possible. The goal is to increase Whites mobility and control of space and to retain the option of where to strike. There are some standard manoeuvers such as c3 and d4,0-0 and Re1,Nb1-d2-f1-e/g3, a4, and others, but Black can often play a <em>big</em> role in deciding the sort of game it will be. He can go for complicated counterattack with the Schliemann, the Open, or the Marshall. He can play more safely, with Steinitz/Steinitz Deferred or more classical approaches like the Chigorin, Keres, Breyer.. In fact one reason NOT to play the Lopez is all of the work required to prepare for everything that might happen. Mastering the Lopez is a lifetimes work.</p>
