The Sydney Airport (ASX:SYD) share price has gained 37% in the last 6 months

The Sydney Airport Holdings Pty Ltd (ASX: SYD) share price has been flying these last 6 months.

Shares in Australia's largest airport are currently trading for $7.91. Over the last 6 months, Sydney Airport shares have outpaced the S&P/ASX 200 Index (ASX: XJO) 37% to 12%. This is despite the challenges the company has faced due to the COVID-19 pandemic.

Let's see what's been happening the last 6 months.

Sydney Airport shares are in the sky

The story that had the biggest impact on the Sydney Airport share price is undoubtedly the $23 billion takeover bid the company received in July.

On the day of the announcement, Sydney Airport shares rocketed 37% to $7.78 each. Since then, shares have gone even higher – reaching a new 52-week high of $8.04 at one point. The company's board ultimately rejected the bid, claiming it "undervalued" the company and was "opportunistic".

The consortium took a second bite of the cherry about 3 weeks ago, but this bid too was dismissed.

Another possible reason for the rising Sydney Airport share price may be increasing optimism among investors about ASX travel shares. Australia's rapidly progressing vaccine rollout is pushing the nation closer to reopening its international borders and ending domestic travel restrictions. This is supposed to happen when 80% of the eligible population has received both doses of an approved coronavirus vaccine. The most recent figures suggest we should hit this number by the end of the year.

You can see this surging optimism in other popular ASX travel shares – at least over the last 5 days. While the ASX 200 has fallen 0.06% in this time. The Qantas Airways Limited (ASX: QAN) share price is up 6.89%, while the Flight Centre Travel Group Ltd (ASX: FLT) is 12.6% higher in this time.

Sydney Airport share price snapshot

Over the last 12 months, the Sydney Airport share price has risen an even more impressive 41.76%. Year to date, shares in the airport have appreciated 23.4%. Sydney Airport Holdings has a market capitalisation of $21.3 billion.