As far as exchange traded funds are concerned, Vanguard S&P 500 ETF (VOO) stands out as a top option for long-term investors to consider. This ETF allows investors to gain exposure to some of the largest companies in the U.

Here are three Vanguard ETFs to buy with $1,000 and hold forever. With that money, you'll gain part ownership in the 500 large U.S. companies that comprise the S&P 500 Index. The beauty of this Vanguard tracking the S&P 500 is that the index is rebalanced regularly.

The Vanguard Growth ETF is highly diversified for lower risk, but it sticks to top growth stocks. Moreoever, it has outperformed the broader index over almost any time frame. A strong investing strategy is to buy the growth ETF along with a standard market index ETF.