All around the city there are bike stations where you can rent a bike. The scheme is the same as the one running in Paris.
Use the touchscreen at the station to subscribe. You will need a credit card to do so. To subscribe costs €5 a week, and you can use the bike for 30 minutes without paying extra. Easy enough in Seville where it rarely takes more than 20 to get from one side of the centre to the other. If you do go over the 30 minute time, you will be charged about a Euro for 30 minutes.
Seville is such a flat city that cycling is easy. And with the hot weather (up to 45 degrees C. in the summer), cycling and the breeze is a lot more comfortable than walking.
There is a downside. Sevici is very popular with residents, tourists, and sadly vandals. Occasionally, either the station is empty, or the bikes have been vandalised. Also you may get to the bike station to return your bike and discover it is full. Log in with your code you were given when you subscribed and you will be able to get another 15 minutes to go to another station. There is a map available on the screen.
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