Toledo is a small town around an hour out of Madrid by train. It has many important historical features as it has existed since Roman times - there are several examples of Roman construction dating back to 1 CE.
These ruins were discovered while renovating a shop. Instead of closing the shop and demolishing the building, a see-through floor has been installed in a clothes shop so tourists can browse hipster fashion and Roman ruins at the same time.
In addition to the Roman ruins there are examples of architecture from the times that Toledo served as a centre of power for the Visigothic church. The current cathedral contains sections from this time.
The Cathedral stands on the site of the old Visigothic church which was consecrated in 587 CE (and some elements of that old church can be seen in the base of the alter of one of the chapels). Construction of the current cathedral started in 1227 and it is an excellent example of Gothic design.
Toledo was also famous for its production of swords and armor - and there are several shops in which you can pick up a suit of full plate and chainmail with a stylish broadsword. Tempting though it was, I decided against such a purchase - something tells me I wouldn't be allowed on the plane ;)
Unfortunately many of the other Toledo monuments (such as the Alcázar) were closed on my visit (due to it being a Monday in the middle of winter), but the town is beautiful in and off itself and definitely worth visiting.