Few trek options you can choose from mumbai/pune
1)Devkund Waterfall trek

Looking for that perfect waterfall hidden inside the jungle which is unknown to the world you can join Treks and Trails India and visit the Devkund Waterfall located near Bhira Village, Devkund Waterfall is one of the most beautiful waterfalls in India. Devkund Waterfall is a mostly unknown and unexplored waterfall in Maharashtra.
https://www.treksandtrails.org/tours/devkund-waterfall-trek
2)Korigad fort trek

Delight in the gorgeous trek to Korigad Fort, located around 20 km from Lonavala in Pune District. Constructed way back in 15th century, this beautiful-historic fort is located at a soaring height of around 929m above the sea level. Part of Shivaji’s legacy, this fort held an integral role during his reign
https://www.thrillophilia.com/tours/trek-to-korigad-lonavala
3)Rajmachi Trek

Rajmachi is a small village in the rugged mountains of Sahyadri in India. The fortification at Rajmachi consists of two forts , namely Shrivardhan fort and Manaranjan Fort. Rajmachi Fort is a popular trekking destination. It is a very famous fort located near two famous hills of Maharashtra, Lonavala and Khandala.
The other route is from Lonavala, which is almost a plain walk of about 15 km. In rainy season this region all the more beautiful with silvery waterfalls, streams and lush green forests and meadows.
https://www.thrillophilia.com/tours/trekking-expedition-to-rajmachi-fort
4) Irshalgad Trek (Matheran)

This fort is well known and visited for! ‘Irshal’ means a pinnacle and ‘gad’ means a fort. Hardly found anywhere in History, Irshalgad may have been under the Maratha rule when Shivaji Maharaj captured the regions of Kalyan and Bhiwandi.
https://www.thrillophilia.com/tours/irshalgad-trek-panvel
5)Raigad Fort trek

The fort once served as the capital of Chhatrapati Shivaji, the Great Maratha king, in the 1674. Perched at an altitude of 1350m (4530 ft) above sea level, Raigard Fort falls under the Sahyadri Mountain ranges of India. The main structures inside the Raigad Fort, which today stands mostly in ruins, comprise of the Queen's Quarters, the Public Durbar, Watch Towers, Darwazas (gateways), etc.
https://www.thrillophilia.com/tours/one-day-trek-to-raigad-fort-maharashtra
6)Tikona Fort trek

Tikona Fort, also renowned as Vitandgad fort, Tikona Fort means triangle fort, .The fort’s mammoth entrance is a special attraction. The Tikona fort is a great trekking destination for the adventurous tourists. One can get the eye-catching views of the Pawna Dam and the forts at Visapur, Tung, and Lohagad. The fort encloses a lake, Satvahan caves and the temple of 'Trimbakeshwar Mahadev'. The fort was built during the Silhara dynasty. There is a temple on top of the peak. The view of the Pawna dam, Kathingad, and valleys from the top is breathtaking.
https://www.treksandtrails.org/tours/trek-to-tikona-fort
7)Raireshwar trek

Raireshwar is situated in Bhor Taluka near Pune, India. Raireshwar has a temple famous for its historical importance.
The temple is very old and of stone structure, but it was later re-constructed in 18th century.
Chhatrapati Shivaji Maharaj took the oath of Hindavi Swarajya in this temple at the age of 16 in 1645 and then created history.
Its said that he had cut his little finger and taken the oath by dripping blood onto the Shivling.
Thus, Raireshwar can be considered as an important place in Maratha history. It is situated in between various hills and forts such as Kenjalgad.
The Route from Korle Village around 6 kms leads to the top of Raireshwar.
You can enjoy many waterfalls on the way. Raireshwar Platue is full of variety wild Flowers.
https://www.thrillophilia.com/tours/trek-to-raireshwar-kenjalgad-fort
8)Mahimatgad Fort Marleshwar Waterfall

Mahimatgad is one of the best jungle treks available in Sahyadri. It is situated in the remoteness of Konkan. Apart from having a nice jungle, it is one of the offbeat treks where rarely do people visit and hence you get real experience of wilderness. For those who are interested in bird or butterfly or general photography this is the perfect trek.
Marleshwar Waterfall is located in Marleshwar of Ratnagiri district. It is a cave temple and is circumvented with sacred grooves. The presiding deity is Lord Shiva. Near the temple, Dhareshwar waterfall can be seen. Local belief is that Lord Parshuram laid the foundation of the temple.
9)Lohagad fort trek

It is said to be the best trekking route near Mumbai and Pune for beginners. It is an easy trek filled with fun and beauty. You will get to see many beautiful things during this trek and after reaching the peak you can see four doors The first one is called 'Ganesh Darwaaja', the second one is called 'Narayan Darwaja', the third one is called 'Hanuman Darwaaja' & the fourth one is called 'Maha Darwaaja'. Out of this Hanuman Darwaaja is the most ancient of all the doors. Between Narayan & Hanuman Darwaaja there are two godowns which were used for storage purpose as a granary.
https://www.thrillophilia.com/tours/one-day-trek-to-lohagad-fort
10)Mahuli Fort Trek

A good one day Trek near Mumbai, Mahuli is at 2815ft above sea level . It is the highest point in Thane district. A popular trekking choice and a paradise for rock-climbers because of its pinnacles. This mountain complex is actually a group of two or more hills with common cols and pinnacles. The forest surrounding Mahuli has been declared as a sanctuary
https://www.treksandtrails.org/tours/mahuli-fort-trek-near-mumbai
https://www.thrillophilia.com/tours/mahuli-fort-trek-thane
Few trek companies that organise treks are .Thrillophilia and Treksandtrails