>>1304673Because the floors are very low. The floors are pretty much exactly the same height as the platforms you can see in some pics. Most other trains have much higher floors.
One of the defining features of Talgos is that they don't use regular bogies. They have just one axle between each two cars (and one single axle at each end). You can see this in the last pic. The train is kind of suspended from a sort of columns above the axle. So the support for the train isn't below the floor level as it would be on regular trains. I didn't take a pic, but the passages between cars are quite narrow, as the suspension type support is situated there.
In some subsequent Talgo trains (don't know if all of them), starting with the following type IV sets in 1980, they further developed this system to allow a passive tilt. Talgo IVs are still in regular service on very few lines in Spain. I rode one from Seville to Barcelona like two or three years ago.
