The Borovets ski resort is only 70 km from Sofia and it is the closest ski resort to the capital of Bulgaria.
The easiest and cheapest way to get there on your own is to catch a shuttle bus that leaves from the Southern bus station (Autogara Yug) in Sofia.
If you arrive in Sofia by plane, then you are in luck, this station is located near the airport.
You can get to it by bus or subway. If you have chosen a bus, then route 84 or 604 is suitable for you, look at Google maps for stops, and if you decide to take the metro, you need to take the Sofia Letishche station (it is located next to the T2 terminal) and get off at the Joliot-Curie station , this station is 350 meters from the South Bus Station (Autogara South).
From other parts of the city you can also take the metro. By the way, the fare in the Sofia metro is just 1.6 leva.
At the Southern Bus Station in Sofia you need to take a bus to the city of Samokov. They go often (every half hour), see the schedule on the official website. The fare is from 4.50 to 6 lev, depending on the carrier company.
Next, at the bus station in Samokov you need to transfer to a minibus to the resort of Borovets. The ticket price is about 2 lev. A minibus stops near the Samokov hotel.