Well, there is a lot that can be written about this beautiful coastal town. Of course the limitations being MS space limitations, my knowledge & vocabulary.
Theres something about St. Marys island?
... that this beautiful island with natural rock formation has not been given its due by all previous reviewers. Originally called Thonsepaar island by locals before being re-christened by the British this island has been the spot where countless Kannada & a few Hindi movie songs have been filmed.
It is a paradise for nature lovers & people who want to escape from the hustle-bustle of the cities to a quieter place. A good picnic spot.
I have heard there is a government boat facility to reach this island. But my experience has always been going there small boats canoed by the fisher men. Quite an experience in itself but not for the weak of heart or people having sea sickness.
The price of course varies based on your bargaining with the fisher men & their mood.
Of course the beaches ...
Summer sands, Panambur, Malpe .... form part of the very limited coastline along the bluish Arabian Sea that belongs to state of Karnataka.
Especially the narrow islands formed by fertile soil where river Netravati (main river supplying water to Mangalore) joins Arabian sea. The only way to get here is through the fisher mens boats.
I think KSTDC (Karnataka Tourism dept) can earn lot of revenue by introducing water sports near the beaches.
But a word of caution to outsiders.The sea along Mangalore coast has very deep whirlpools which can suck in whole tourist groups. Unfortunately no ones bothered to post a warning about these or demarcate the danger spots. A lot of tragedies involving tourists happen because of lack of warning signs.
And the sea is extremely harsh during monsoons & avoid swimming in the late evenings & days closer to Full Moon (when the tides reach their peak).
The people & culture ...
Tuluvas
The native Mangalorean language is Tulu. The main language spoken & understood by the majority. Unfortunately this beautiful language lacks alphabets of its own & often dependent on Kannada alphabets.
The culture of Tuluvas is matriarchal. The family lineage is traced from Mothers side (Mother, granny etc.). Inheritance was from uncle to nephew (Aliya Santaana) similar to Keralite Nayar culture.
Worship of ancestors, spirits of warriors & other great men/women, Nagas (snakes) forms the original culture of Tuluvas. The main spirits worshipped are Koti-Chennaya, Panjurli, Karluti, Siri, Ali (Muslim spirit!) etc. Boothada Kola is performed to pacify these spirits ; seek their blessings & protection. There are Boothama Sthanas & Naga Sthanas devoted to spirits & snakes.
Traditionally Wrestling (practiced in Garadis) is the popular sport, followed by Cattle racing (Kambla) & Cock Fighting.
Yakshagana popularized by Dr. Shivram Karanth is the traditional dance-drama art with head gear & costumes similar to Kathakkali with thick make up. This vanishing art form is more popular in the rural areas.
The most popular Hindu temple is Kadri Majunatheswara Temple the oldest (shaivite) temple in Mangalore. Built by the legendary Jogi of the Naath panth (sect) Mathsyendra Naath Maharaj. This temple has udhbhava (natural) lingams surrounding the temple (becareful while walking). Other than sanctum sanctorum & deities; the other places of interest are Gomukh Thirtha ( water spring from the mouth of a cow statue), the cave of Pandavas believed to lead all the way to Hardwar, Kashi etc. & Sita Bhaavi (well of Sita)
Legend has it that the main lingam (symbol of shiva) of famous Dharmasthala temple was taken from here by Annapa Panjurli Daiva (spirit). Car Festival of this temple is the oldest & most important festival of Mangalore.
Then there is Mangala Devi temple which gave this city known as Kudla. Kodial, Mangalapuram, Maikaal, Manjuran (arabic) the current name.
Other important Shakthi (Devi) temples are Katilu, Polali, Kolluru, Konchadi etc. Manjeshwara, Subramanya etc. Naga temples. Sharavu Shiva-Ganapathi temple. The legends related to these temples will require me to write books to do any real justice. There are innumerable other important temples left out for lack of space.
Kudroli Gokarnanatha Temple renovated (at cost of crores of rupees) recently & inagurated by then PM Rajiv Gandhi is the most beautiful modern temple in Mangalore.
Konkans
The second major language is Konkani spoken by Konkani Brahmins (only fish eating brahmins other than Bengali brahmins) & Catholic christians of Goan origin. Though Devnagari (Sanskrit) is official script for Konkani language, most of Konkani literature in Mangalore uses Kannada script.
The Konkani Brahmins are vaishnavas & their main temple is Venkatramana temple in Car Street. The Car Festival of this temple is one of the important festivals in Mangalore attended by thousands of devotees. Dhaali Thoy (special kind of Dhaal) is a speciality served in this festival.
The Konkani christians are Catholic & many educational institutions & hospitals of fame are run by the church. The most beautiful church is St. Aloysius Church with paintings by an Italian artist (restored by Archaeological survey of India). The other popular churches are Milagres Church, Bendoor church etc.
Other Mangaloreans
The third being state language Kannada. The Kannada spoken here is bookish (as written) & with a liberal mixing of Tulu words. Being on the border with Kerala Malayalis form the fourth largest linguistic group (Again the Malayalam spoken by them is infamous as impure Kasargod Malayalam the way Mangalore Kannada is infamous in Karnataka).
The Muslims in Mangalore are also culturally diverse. Beary (merchant) muslims who speak Beary language which is mixture of Tulu, Malayalam & Arabic. Moppila muslims speak a mixture of Malayalam & Arabic. Navaayat muslims speak Konkani & then there are Urdu speaking Deccani Muslims
Important places...
The Sultan Batteri or Fort of Tipu Sultan where he kept guard against British ships is a place of historical importance.
Karnataka Regional Engineering College in Surathkal. Mangalore Refinery & Petrochemicals Limited (MRPL) infamous for polluting Mangalore environment.
Staying...
Middle Class families : Hotels Ayodhya, Wood Side, Wood Lands, Srinivas, Panch Mahal
Costlier hotels : Taj Manjuran, Moti Mahal
Moving Around ...
Mostly in private buses. Govt. buses also ply to most of the nearby small towns. Better avoid Autos (roads are full of craters). Private cars often with drivers are available for rental.
Something for the Black Hole ....
Since Mangalore is a coastal town Fish forms the staple diet of most people. Vegetables are costlier here compared to fish during season after the monsoons. Mangalore also has the only major Fisheries college in Karnataka.
Non-veggies should savor the Kori Rotti-chicken curry, spicy chicken Puli Munchi, Pomfret (Fish) Masala Fry, Chicken Sukka etc.
Mangalore is the birth place of Udupi hotels famous all over India for Masala Dosas, other variety of tasty Dosas , Idlis & other South Indian veggie delicacies. Do not forget to taste Biscuit Ambode, Biscuit Rotti, Goli Baje etc. (at Taj Mahal hotel at Hampankatta)
So you are tired & dont get sleep, Shendhi a country liquor prepared from coconut sap is as notorious here as Goan Feni (prepared from cashew).