Inherited Turn
MM Seville. Fire the entertainer and put the city so production on Sistine is in 34 (3 turns earlier).
Decide everything else looks in order, so I hit that enter button.
270
IBT
Hittites declare on the Persians
Madrid: University->Worker. Madrid has finished all possible culture and I have heard nothing to the contrary so I am going to turn Madrid to worker production. If you guys think this a bad idea, merge them all back at a minimal loss of production.
280
IBT
Toledo: Colosseum->University
290
Shortrush Salamanca's Colosseum via a Marketplace. Due now in 3. With a Colosseum we will be able to drop taxes to 10%.
IBT
Music Theory->Astronomy, due in 11.
Our palace now has phalluses... phallusis? phalli? Spires!

Our palace now has spires.
310
Think better of things, and switch Toledo from its University to J.S. Bach's. Due in 40, but with its many hills currently being mined, it should actually be a lot sooner.
IBT
Salamanca: Colosseum->University
Americans and Koreans enter the Middle Ages
320
Sliders to 4.5.1
IBT
Barcelona: University->Palace, Pre-build for Copernicus. However, I believe we should consider trading for Feudalism and building Sun Tzu's here.
I gave our palace lawn some trees.
Koreans are buildilng Sun Tzu's.
350
That's about that. Santiago's Colosseum and Murcia's University are due to finish on the IBT. I probably should have focused less on optimizing size-12 cities and more on bringing Valencia up to speed, but as it was I did most of my work around Toledo. There is a worker SE of Santiago roading to the Gems. He'll be at that a while unless we want to divert one or two more to help him. All the new workers I've pumped out of Madrid have gone to Valencia, but it needs a lot of work. It has stalled in growth. The stack of four workers north of it will finish chopping in two; in the year 360AD make sure to move a citizen to work that tile so we get that extra food upon chop completion.
I just noticed -- next person should switch Valencia immediately to a Cathedral. The aquaduct will not be needed more many turns to come; we still have jungle to hack. A cathedral will (luckily) be completed with just 2 more shields. The additional culture cannot be denied!
I think we should trade Korea Mono for Feudalism and build Sun Tzu's in Barcelona. They are no risk to beat us to any wonder in the upper tier and they have started Sun Tzu's themselves.
Madrid's estimated 20k culture is in the year 2018. Pyramids should be doubling in culture soon. Estimated 100k is 2152, so we still have a ways to go. Barcelona's 20k is 2115 -- another reason why I believe they should make Sun Tzu's and save Copernicus for a lower-culture town.
Estimated culture in 2050AD (courtesy of SirPleb's culture calculator):
Madrid -- 21,776
Bracelona -- 17,211
Seville -- 8,287
Toledo -- 7,926
Santiago -- 6,455
Salamanca -- 7,804
Murcia -- 6,418
Valencia -- 3,987
A grand total of 79,864!