By road
There are three established routes into the park.
The Probolinggo → Ngadisari Route (Cemoro Lawang And Mount Bromo)
The nearest larger town is Probolinggo, on the north coast of Java about 45 km as the crow flies from the park but it feels a lot further. This is by far the commonest route used to access the park as it is the most straightforward but not necessarily the most interesting. About 6 km west of Probolinggo on the main coastal highway, turn south at the village of Ketapang. From there the road snakes up for 40 km through Sukapura not a bad idea to stay the night here as the hotels are good to Ngadisari and finally Cemoro Lawang on the edge of the caldera. Total journey time about 1 hour and 30 minutes.
To get to Probolinggo from Surabaya, take a Damri shuttle bus from the Juanda International Airport in Surabaya to the Bungurasih bus terminal also called Purabaya in the city. Then take an express Patas air-conditioned bus for the 2 to 3 hr journey from Surabaya to Probolinggo about Rp 25,000.
Green Mini-Buses 10 seats from Probolinggo to Cemoro Lawang are located right outside the terminal: Rp 250,000 translates to Rp 25,000 per passenger. Departure from the the terminal bus station as soon as the bus is full or someone pays the full price. Can delay the bus up to 2.5 hours to get enough passengers though after 4pm it's quite hard to get enough passengers, its possible to negotiate for a whole minibus at Rp 200,000. However, the drivers can sometimes be less demanding for return trip back to Probolinggo, and can start out with fewer passengers on board.
The Pasuruan → Tosari Route
This route is only a little harder than the Probolinggo option and Pasuruan has the benefit of being closer to Surabaya. From Pasuruan on the main north coast road between Surabaya and Probolinggo, take the road 45 km south to Tosari via Pastepan. Irregular buses ply this route or you can drive it in a regular car. From Tosari to Wonokitri it is another 3 km via a local bemo or on the back of a truck. From Wonokotri up to Bromo it is a really nice three hour 14 km trek, so you do need to start very early if you want sunrise. Alternatively you should be able to hire a 4x4 with a driver for that journey. There is accommodation in both Tosari and Wonokitri.
By plane
The nearest major airport is in Surabaya IATA: SUB, three to four hours away by car and more by bus. Surabaya is well served by regular domestic flights from Jakarta and Bali and some other countries in Asia.
Abdul Rachman Saleh Airport IATA: MLG at Malang is a small regional airport with flights from Jakarta only and access from here makes sense if you intend to enter the park via the Tumpang/Ngadas route.