Ar�valo
An ideal place to start the route is in this noble town in the north of the province of Avila and on the edge of those of Valladolid, Segovia and Salamanca. Isabella I of Portugal lived the first few years of her life in the Casas Reales, a place that converted Ar�valo into the Court and the centre of major political intrigues. Other important monuments are the church of Lugareja and the plaza de la Villa.

Madrigal de las Altas Torres
This is where the Catholic queen Isabella was born in 1451 in what is now the Monasterio de Nuestra Se�ora de Gracia. Some rooms from that period still remain, as does the royal stone staircase with a wooden mudejar finish; the Sala de Cort�s; the Sal�n de Embajadores; the Capilla Real and the room where the queen was born. There are also various documents, objects and pieces of furniture.

Medina del Campo
Queen Isabella died in this town in the province of Valladolid in 1504. Its historic centre contains a myriad of monuments that are testament to its noble past. One of the most prominent is the Castillo de la Mota, an impressive brick fortress and one of the largest and best preserved in the region, with the highest keep in Castilla y Le�n. Other important buildings are: the Palacio de las Due�as, the Colegiata de San Antol�n; the churches of San Miguel and Santiago, Santa Mar�a la Real and Santa Clara de Santiago; the Hospital de Sim�n Ruiz and the Convento de la Magdalena.

Tordesillas
Tradition states that the streets and stones of Tordesillas hold the most secret feelings, passions and hates of Do�a Juana I de Castilla, known as Joanna the Mad. The most important monument is the Real Monasterio de Santa Clara, belonging to the Patrimonio Nacional and declared of National Cultural Interest. Not to be missed are its Arab patio, the baths or the Golden Salon. The church was built in the second half of the 14th century and is gothic in style. Other essential stops are the Plaza Mayor, the bridge, the walls and the churches of Santa Mar�a, San Pedro and San Juan; the Convento de San Francisco, the Hospital de Mater Dei; the Houses and Museum of the Treaty of Tordesillas, where the Catholic Kings and the kings of Portugal agreed on the frontiers of the lands and seas of America.

Simancas
Its lookout over the river Pisuerga is the perfect spot to end this tour. Its main monument is its castle, an architectural gem built in the 15th century by the Almirantes de Castilla. It was later handed over to the crown, which enabled subsequent monarchs to reform it and adapt it to their tastes. It currently houses the Archivo General de Simancas, one of Europe's most important historical archives.