Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Date | Course | Distance | Type | Winner |
| --- | --- | --- | --- | --- |
| 30 August | Granada | km (mi) | Team time trial | Liquigas |
| 31 August | Granada to Jaén | km (mi) | Flat stage | Alejandro Valverde ( ESP ) |
| 1 September | Jaén to Córdoba | km (mi) | Flat stage | Tom Boonen ( BEL ) |
| 2 September | Córdoba to Puertollano | km (mi) | Flat stage | Daniele Bennati ( ITA ) |
| 3 September | Ciudad Real | km (mi) | Individual time trial | Levi Leipheimer ( USA ) |
| 4 September | Ciudad Real to Toledo | km (mi) | Flat stage | Paolo Bettini ( ITA ) |
| 5 September | Rest day | Rest day | Rest day | Rest day |
| 6 September | Barbastro to Naturlandia-La Rabassa ( Andorra ) | km (mi) | Mountain stage | Alessandro Ballan ( ITA ) |
| 7 September | Escaldes-Engordany (Andorra) to Plá de Beret | km (mi) | Mountain stage | David Moncoutié ( FRA ) |
| 8 September | Vielha e Mijaran to Sabiñánigo | km (mi) | Intermediate stage | Greg Van Avermaet ( BEL ) |
| 9 September | Sabiñánigo to Zaragoza | km (mi) | Flat stage | Sébastien Hinault ( FRA ) |
| 10 September | Calahorra to Burgos | km (mi) | Flat stage | Óscar Freire ( ESP ) |
| 11 September | Burgos to Suances | km (mi) | Intermediate stage | Paolo Bettini ( ITA ) |
| 12 September | Rest day | Rest day | Rest day | Rest day |
| 13 September | San Vicente de la Barquera to Alto de El Angliru | km (mi) | Mountain stage | Alberto Contador ( ESP ) |
| 14 September | Oviedo to Fuentes de Invierno | km (mi) | Mountain stage | Alberto Contador ( ESP ) |
| 15 September | Cudillero to Ponferrada | km (mi) | Mountain stage | David García ( ESP ) |
| 16 September | Ponferrada to Zamora | km (mi) | Flat stage | Tom Boonen ( BEL ) |
| 17 September | Zamora to Valladolid | km (mi) | Flat stage | Wouter Weylandt ( BEL ) |
| 18 September | Valladolid to Las Rozas | km (mi) | Flat stage | Imanol Erviti ( ESP ) |
| 19 September | Las Rozas to Segovia | km (mi) | Mountain stage | David Arroyo ( ESP ) |
| 20 September | La Granja de San Ildefonso to Alto de Navacerrada | km (mi) | Individual time trial | Levi Leipheimer ( USA ) |
| 21 September | San Sebastián de los Reyes to Madrid | km (mi) | Flat stage | Matti Breschel ( DEN ) |
| Total | Total | km (mi) | km (mi) | km (mi) |
Question:
What is the date for the La Granja de San Ildefonso to Alto de Navacerrada course?
Answer:
20 September