Slovenia requires all motor vehicles travelling on its highways to have a vinjeta sticker. This system exists in lieu of tolls, and the vinjeta can be easily obtained at nearly all petrol stations and kiosks. Yearly/monthly/weekly stickers cost €110/30/15 for cars and yearly/half-yearly/weekly ones are €55/30/7.50 for motorcycles. Also be aware that the border police will likely not remind you to purchase a vinjeta when entering the country, but are extremely likely to issue you with a steep fine when leaving if you've failed to do so. For more information, check www.dars.si.