Taxi service to Cagliari is provided by the following companies:
Cooperativa Radio Taxi “Quattro Mori”, Scalette Santo Sepolcro 2, ☎ .
Cooperativa Radio Taxi “Rossoblù” (Via Duomo 19), ☎ .
ARST. Bus service to the city is provided in the daytime by ARST Azienda Regionale Trasporti (free toll 800 865042, info 070 4098327).
Train Station. There are direct connections to Sassari
By public transportation
Cagliari Public Transportation CTM provides an fast and efficient service to get around in Cagliari city and suburbs.There are about 30 lines of buses and four new metro lines are in progress. At least the bus traffic is amazingly efficient and reliable to Italian standards. Daily passes cost €3 each and allow unlimited riding on buslines in Cagliari as well as on the light rail tram that runs from Cagliari to Monserrato. 
It is really difficult to get parking and drive in rush hour even if the road network has been recently improved.
The best thing you can do is walk through the old city and discover it. Almost everything you have to see in a quick visit of Cagliari can be reached by a pleasant little walk. Plus there are some spectacular views, for example of the Gulf of Cagliari seen from the old city that are best seen from points that are not reachable by car.
Wear comfortable shoes, though. The old town of Cagliari is somewhat hilly, so you will be walking uphill or downhill most of the time.
There are clean public toilets in the building on the Pontile Sanita ferry wharf, near the bus terminal.
The Cagliari bike station is in the centre of Cagliari, inside the parking area, at the train station. 
You can download audio guides and PDF guides from the Cagliari tourist website  organized for six walking tours in diffent areas of Cagliari.
The Old Town lies on top of a hill with a view of the Gulf of Cagliari.
- Art deco architecture
Ghetto degli Ebrei (Comunial Centre for Art and Culture Il Ghetto), Via Santa Croce 18, ☎ . Tu-Su 10.00-21.00. Displays about artichecture and city planning. Nothing about the ghetto. free.
Torre dell'Elephante. 10:00-20:00. medieval tower €3.
Saint Pancras Tower (Torre di San Pancrazio). Tu-Su 09:00-17:00. Built in 1305, during the Pisan domination of the city, by the Sardinian architect Giovanni Capula, who designed also the Torre dell'Elefante. Good view over Cagliari from the top. €3.
Cathedral of St. Mary and St. Cecilia (Cagliari Cathedral), Piazza Palazzo 4/a. Beautiful 13. century church. Do not miss the Shrine of the Martyrs, excavated out of the rock. free.
Bastione di Saint Remy (Piazza Costituzione). This impressive fortification was built in the late 19. century. Climb the huge stairways to be rewarded by a stunning view of the city, the sea and the mountains. Or use the Elevator. free.
Palazzo Reale. This was the residence of the royal representatives during the 14th century. free.
You must have a full relaxing day on the wonderful Poetto Beach. This 8 km beach will excite you and is perfectly equipped to satisfy every your wish. You can get here by buses PF, PQ, 3P, and 9P.
The beach is divided to the free parts and the beach clubs, the latter charging you with an entry fee but rent umbrellas, deck chairs, etc. for you. Prices are around €3/entry, about €12 for an umbrella, a deck chair and a sun bed. The club beaches clean the sand each night and provide you with showers and toilets.
Most of the shops are concentrated in a couple of areas: Via Roma and Largo Carlo Felice, the pedestrial roads Via Manno and Via Garibaldi, and the part of town around Via Alghero, Via Paoli and Via Dante. Lots of beautiful shop are concentrated in this areas which could remind you of Copenhagen's Strøget.
There are many of restaurants in the old town area, and you probably will not make a bad selection anyway since the food seems to be top class at least if you enjoy seafood. A dinner for two with little house wine.
l'Oca Bianca, Via Napoli, 38 (Marina District), ☎ . A good pizza place tucked away in the side streets. Make a reservation, though.
Glitter, Via dei Genovesi, 22 (Castello area). If you want to taste another kind of typical Italian food, try piadine at this place. This small café has a unique atmosphere that recalls medieval times with its stone walls and you can admire a Punic cistern under your feet while tasting delicious piadine.
There are a few places to enjoy lunch salads at the Piazza Yenne and wonderful Gelaterias if you don't want to eat too heavily during the day. These places double up as decent eateries by night.
Caffe degli Spiriti, Bastione San Remy (on top of Bastione San Remy), ☎ . Sardinian specialties, salads, pizza, ham etc. At night cocktails and loungebar. Great view over the city and the ocean.
Cafe Restaurant Van Gogh, coastal road Cagliari Villasimius km 19,4, ☎ . Traditional Sardinian food that is freshly prepared and beautifully presented, afternoon light meals and salads, lunches and dinners, prix fix lunch menus, Facilities for children, Good parking, Close to beach
The whole area around Cagliari gives host to a number of accommodation options including the world famous Forte village , and the stunning hotel Le Meridien Chia Laguna on the white sandy beaches of Chia.
Hotel Tanca Irde. Strada per Poggio dei Pini Capoterra, 09012 CA. Hotel Tanca Irde is located on a small hill between the mountains and the sea, within the area of Capoterra, a few kilometers from Cagliari and its airport. The hotel, which is open all year round, is surrounded by ample grounds containing a swimming pool and private car park.
Hotel Palladium, Viale Europa (Monastir, close to the SS131, well served by bus), ☎ , fax: 0039709168013, e-mail: email@example.com. The hotel is outside the city. It provides 24 h reception, free Wi-Fi access, an outdoor swimming pool, a nice garden, and a free secure parking garage. The rooms are comfortable and quiet, the staff welcoming and helpful.
Left luggage (In the bus terminal, at McDonalds). There is no left luggage service at the train station, but the bus station is next to it. It is also only a short walk from the ferry terminal. €1/hour.
Free WiFiCa. Free wireless internet, without registration in the historic center and at the train and bus stations. In general if you have a good view of the city you can get online. free.
- Alghero, also known as Barcelonetta (Little Barcellona) is pretty city with a strong Catalan influence, and is also known for its beautiful beaches and very good food at reasonable prices (4 h bus trip from Cagliari).