One of the highlights of the Costa Blanca. Beautiful surrounding beaches, mountains, forests and valleys. Fantastic town, beautiful architecture in the centre, great restaurants and bars, plently to do.
Denia is an authentic, working town and whilst it has plenty of tourists and expats it doesn't feel overwhelmed.
I personally love Denia as a destination, but it may not be for everyone -
The nightlife is good in terms of atmopshere, bars, restaurats and shops open late. It is particularly good during festivals like the 'Bous Al Mar' event in July. However if you're looking for clubbing as per Berlin/ Ibiza/ Mikonos this is not the place for you.
If you're looking for somewhere with very easy right beside the airport, it's not for you as the nearest airport (Alicante) is over a hour's drive.
If you want somewhere that caters specifically to tourists and where everyone will speak English/German/Dutch etc etc... this is not the place for you.
Hope this helps, VIVA DENIA!