We've had a few people ask about driving from Barcelona so thought I'd add the route I take - it might not look the shortest on the map but works out best because it's good roads (and toll free).
- Leaving Barcelona you want the A2 in the direction of Lleida
- You'll see a sign for Andorra after not too long ... but ignore it!
- You want to come off at junction 523 (this is kilometre number 523) signed Cervera Sud **
- Very soon after take a right turn on the L311 signed Cervera & Guissona
- You'll come to a big roundabout - follow Cervera/Guissona/Ponts/Andorra
- Continue to Guissona then take the L313 signed Ponts (it's not signed Andorra)
- At Ponts, Andorra is signed on the C14 and will continue to be signed
- Once you've crossed the border in to Andorra follow signs for Ordino & La Massana
- From La Massana it is signed Arinsal