Mar del Plata is the second most visited city in Argentina after Buenos Aires, but the majority of its visitors come from within the country. It has a complex and large infrastructure for tourism including hotels, beach clubs, restaurants, casinos, golfs and sports venues.

There is no trains nor tube here, only buses and they are not that good. So the best you can do is to hire a car. If you come by plane you can do it at the airport. If you are brave and willing to practice your Spanish, then you can use some of the buses, which are quite cheap. Number 221 goes along the cost so one ride would be a good and cheap tour.
“The” coastal tour
*) The best spot to start a coastal tour in the southern end of the city, and drive all over the coast, stopping in the places/beaches you like. Here you can find the best beaches of the city according to all the locals, the so-called “playas del sur” (southern beaches). Some of them are La Reserva, La Caseta, Mirador 9 and Mute. I strongly recommend the latter. It has more space and facilities and it is less crowded. They also organise events bringing national and international artists such as Marco Carola, Solomun, Above and Beyond and John Digweed.
*) The second point of interest (heading north) is the city’s lighthouse. Next to it there is an aquarium called “Aquarium“. Then you can get into the pier/port. There you can walk to a wharf (“fishermen wharf”) where there are a lot of little yellow ships and you can also see another wharf full of seals (a special type, called “marine wolf”). Then you have plenty of restaurants to eat good and fresh fish. I would recommend Viento en Popa or Virazon. (For a good summary of the food you must try in Argentina check out this post).
*) Then you keep driving north and you will pass the golf club and then you will get to “Playa Grande” (big beach). It’s the most famous beach in the city. It is always overcrowded but it is nice. In the south end of it, there is a place called Quba, one of the best spots in the city. You can eat and drink during the day or night looking at the sea, and you can also dance and meet locals from 1am until around 6am, just in time for the sunrise.

*) You keep driving north and you will pass a park and in front of it a beach with rocks. Then you will see another good place to eat called “Manolo“. There you MUST eat “churros con dulce de leche”.

*) Keep driving again you will pass the Casino. The beaches at that point are not that nice. In front, you have a fountain with lights (good to see during the night). And you have the only pedestrian only street called “Peatonal San Martin”. I don’t like it but it is a touristic place.
*) Keep driving again you get to “Avenida Constitucion”. And there you will find a modern art museum.
All that journey can take one full day or the whole weekend, depending on the time to spend at the beach or restaurants. The following map shows the full path.
More places to visit
*) Guemes Street. Is the street where Saint Jeanne hotel is. There are good shops, coffee shops, and pubs. Again you must eat medialunas (croissants) from Atalaya or Boston patisseries. You should also visit Antares which is the best beer of the city, and probably of the whole country. And don’t forget to try alfajores Havanna.
*) Alem Street. It is next to Playa Grande beach. There are some good coffee shops and restaurants as well.
*) The best Asado (Argentine BBQ) can be found in Pehuen. You must try the following: chorizo, morcilla, molleja, chinchulin, matambre de cerdo. It can be a one in a lifetime experience if it is your first time in Argentina, and you like meat.
*) The most sophisticated restaurant is Sarasa Negro.
*) If you still have time and the weather is not sunny and hot as usual, you can go 15 km into the countryside and find Sierra de los Padres. You can drive around a few hills and there are good places to have afternoon teas. There is also a golf club and a very beautiful boutique hotel such as La Rocchetta.

Where to stay
If you have enough budget, there a few 5 stars hotels such as Sheraton, Costa Galana, Hermitage, Provincial (the last two are not that expensive, all of them by the coast). And one 4 stars hotel I would recommend is Saint Jeanne.
Otherwise, you can find all kind of hotels, flats, guesthouses, etc. I would recommend staying close to Guemes Street or Playa Grande (if possible) and not in the city centre. Booking.com or Airbnb can help you.
I think you have enough with this. Be patient with the traffic, but if you drive in Buenos Aires first, here you will be ok. Drivers will not let pedestrians cross the streets and they will not respect the roundabouts, among other things.
Where to eat
Check our “Best restaurants in Mar del Plata” post to find the best places to have all kind of food in town, including coffee, ice-cream, pastries, beer and more.
To have a better idea about Argentinean food, you can read about its traditional cuisine in this post.
Buen Viaje!