There are many in the travel industry who look back fondly on the Glory Days of SEO - the era before Google starting making changes to its search pages.
The apparent golden age of digital marketing let travel brands focus solely on two things: optimising pages based on their content, so they could appear as high as possible in natural search results; and bidding against competitors on keywords so that their text ads would appear on the right-hand side of the organic results.
This period actually lasted a fairly long time, at least in web terms, but things started to change at the turn of the decade.
A flurry of additions to SERPS (search engine results pages), especially on travel-related search queries, saw the appearance of elements such as maps, local information, images, videos and Wikipedia data.
And then came Google's own services, such as modules for Google Flight Search and Hotel Finder.
Later items include Twitter cards, Google News-sourced articles and the Knowledge Graph.
Google's search results pages, in short, have changed dramatically (albeit gradually) from how they looked half a decade ago.
Digital marketing software provider SearchMetrics recently analysed page one of Google SERPS for half a million frequently searched terms to understand how much the real estate has changed.
One of the top-line findings is that the number of organic links displayed on page one has fallen from the original ten to around 8.5, with the real estate taken up with other modules and items.
In addition, almost every search query now produces at least one related image, video, Twitter card, or news item.
But SearchMetrics found there are some major differences in how SERPS work on desktop and mobile devices.
EMEA marketing director, Lars Hartkopf, says:
"Gone are the days when optimising for search was all about trying to appear in the classic ten blue organic links on Google’s first page.
"Now marketers must also plan their strategies to include opportunities around a variety of Universal and Extended Search boxes, understanding how to create and optimise content which Google will consider useful for each."
So, what can digital marketers do about it?
SearchMetrics came up with five areas to look at:
1. Integration boxes
Google is probably trying to discourage image-laden pages with long download times (often a key feature of travel websites), so is less likely to feature them in organic results.
Mobile results also include more Google Maps and Twitter Card integrations but fewer Product Listing Ads integrations related to search queries.
Marketers, therefore, should make sure they strike a balance between content types and fully understand the impact of that strategy in SERPS.
2. App suggestions
On mobile searches, Google often integrates what is known as an App Pack box, essentially to show different smartphone apps that are available in the respective Apple of Google app stores that are related to the search query.
Marketers need to ensure that their own application is optimised to appear (using known techniques) in those packs.
It's a virtuous circle, too - the more downloads, the higher the chance that Google will feature it the pack.
3. Video boxes
With around a quarter of search results featuring at least one featured video (nine out of ten, inevitably, coming via Google-owned YouTube), travel marketers have to ensure they do a lot more than produce clips.
To boost the chance of a video being featured against a search term, creators must ensure they include the relevant and optimised descriptions and tags, as well as selecting a thumbnail for the static image and, as has been seen more recently, subtitles.
4. Knowledge Graph
These modules are hugely important for travel brands, mainly as they appear frequently against search terms relating to destinations and attractions within a location.
Google obtains the information from various online sources, allowing known brands to have some influence on what appears when users carry out a search.
Such information includes logos/images, social network profiles and contact information.
Another frequently integrated module is from Wikipedia, although SearchMetrics notes that officially this is a web user-generated page and supposedly hard to control.
5. Direct Answer boxes
These often appear when a user fires up a query that includes the words "how" or "what". Well-placed above organic listings, results are known to generate a fair amount of organic traffic to a website.
Securing a spot there is harder, with content needing to be optimised, resting on a high authority site (page rank) and structured using specific web code.