Slovenia requires all motor vehicles travelling on Slovenian highways to have a vinjeta (veen-yeh-tah) sticker. This system exists in lieu of tolls, and the vinjeta can be easily obtained at nearly all gas stations and kiosks. Yearly/monthly/weekly stickers are €110/30/15 for cars, €220/80/40 for larger vehicles (ie with a height of over 1.3m above the front axis) and €55/30/7.50 for motorcycles. Also be aware that border police will likely not remind you to purchase a vinjeta when entering the country, but are highly likely to issue you a steep fine when leaving if you've failed to do so. For more info check www.dars.si.