There is no difference between the passes except that with the 15 day pass you can travel as much as you like in all countries that are part of Interrail on 15 days in a row. With the 15 days in 2 month pass your 15 travel days can be spread out over 2 months.

The only limitation for both passes is that in your home country you can only travel on a maximum of 2 travel days.

Did this answer your question?

Ok, perfect then with the pass for 15 days in a row I can stay two days in a country perfectly and then take another train to go to another country, right?

Yes, you can travel as you like in the 33 countries that are part of Interrail, except for in Spain if that is your country of residence. If you live in Spain you can only travel on a maximum of 2 travel days in Spain.

HOla, si/yes but NOT in your own home country ES. Also note that RENFE wants you to go to one of their counters and show activated pass to have the always needed RES para su trenes. That is, if you want to take tren in ES-you can also fly out to far away and start using trenes from there.

ON the flexible 15 days you can also use nighttrain till end of trip if you board it before 23.59. Most nighttrains and certainly with sleeper need to be RES.

Estimada Nerea, 

No se si entiendo muy bien tu pregunta, pero en todo caso, con ambos pases puedes viajar cuanto gustes dentro de los países incluidos en el Pase. Ten en cuenta que si tienes residencia en España, deberás seleccionar esta como país de residencia. Sólo podrás viajar durante dos dias en territorio español, para más información, puedes visitar este link: https://www.interrail.eu/es/interrail-passes/what-is-interrail/travel-your-own-country

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Saludos!