Sevilla from May 4th - May 6th (during the April Fair)

'Do you think our trip will be adversely affected by the April Fair, which is from May 5th - May 10th? ' - No.
'We have read that food quality and local service can plummet during this time period. Is this true?' - It is nonsense as far as I am concerned and is a new one on me. Link or where did you read this?
'Also, will restaurants or sights shut down starting on May 5th?' - No.
This is a city of 700,000 plus all who come from far and wide. Everyone does not decamp to the feria. 100,000s still need servicing as usual, as do all who want to see the 'sights'.

And you are planning to go to Feria, right? What a shame it would be to be in Sevilla during Feria and not even go!

Neil - Thanks for your answers. The main source of the "food quality" concern came from Rick Steves' Spain 2014. Specifically, page 659, second paragraph (Helpful Hints > Festivals), "Prices can go sky-high, many hotels have four-night minimums, and food quality can plummet."

Emily - Yes, we do plan on trying to soak up the culture at the April Fair. We are still trying to figure it out, as it sounds like it's a bit of a family affair (i.e. - you may need to know someone).

-Wes

Wes.
Thanks for the thanks.
Regarding the fair. There are certainly six or seven public casetas not tied to businesses or families and the chance, if out that late and can stand the pace, you might be invited in to a private caseta. There is every reason to take a walk around the grounds. A 'google' for images of 'feria Seville' should do it.

Hi
We will be in Seville 2-5th May & wonder if we will get to see any of the fair on 5th or should we stay another night. Have read conflicting reports re the start of the fair, some sites say that the official opening night is not until midnight on Monday, other sites have stated that it can sometimes start unofficially on the Saturday. We would love to see some of the festival but can't really stay any longer than Tuesday 6th.

Any help/thoughts would be most appreciated

Lianne- stay till Tuesday!

The lighting of the puerta ("el alumbrao") happens Monday at midnight. From what I've heard (and seen) it's something not be missed.

See you there :)

Last year, my husband and I arrived in Sevilla the Friday before the April Fair and stayed until Monday morning. If I were to do it over again, I would stay through Monday night. It was exciting to see the Sunday parade of carriages that were filled with women in their flamenco dresses and men in their finery, and there was a neat atmosphere as the city readied for the party, so we didn't miss it completely. The guide of our walking tour made the casetas sound like a wedding, in that it's a party that you're not invited to, of people that you don't know, but you may get invited to crash.