The current offer is to earn 75,000 bonus miles when you spend $4,000 on purchases in the first 3 months from account opening. This is marketed as being equal to $750 in travel. However, by understanding how to use transfer partners, you can get significantly more value (for example, see how I used 67,000 CapitalOne miles to book an $11,000 business class flight here!) 

One of my favorite features is that this card earns unlimited 2X miles on purchases, so I use it for all my spending that does not fit into another bonus category. Additionally, you earn 10X miles on hotels and rental cars and 5X miles on flights through CapitalOne Travel. You also receive a $300 annual credit for bookings through CapitalOne Travel, meaning the annual fee is effectively $95. Another standout feature of this card is lounge access – CapitalOne lounges and Priority Pass lounge access is included. And you will also receive 10,000 bonus miles (equal to $100 towards travel) every year, starting on your first anniversary.