Putting it together

That was a lot of work to describe a single gate. Let’s put everything back together and see what we’ve got.

A few minutes later we had reached the lodge-gates, a maze of fantastic tracery in wrought iron, with weather-bitten pillars on either side, blotched with lichens, and surmounted by the boars' heads of the Baskervilles.

Basically this snippet introduces us to a thing, and describes it in detail:

A few minutes later we had reached the lodge-gates, a maze of fantastic tracery in wrought iron, with weather-bitten pillars on either side, blotched with lichens, and surmounted by the boars' heads of the Baskervilles.

 

It is made up of five clauses:

A few minutes later we had reached the lodge-gates, a maze of fantastic tracery in wrought iron, with weather-bitten pillars on either side, blotched with lichens, and surmounted by the boars' heads of the Baskervilles.

 

But clauses can be broken into smaller word groups.

A few minutes later we had reached the lodge-gates, a maze of fantastic tracery in wrought iron, with weather-bitten pillars on either side, blotched with lichens, and surmounted by the boars' heads of the Baskervilles.


 
This is snippet is easy to read but contains a lot of subtlety. Let’s see if we can write some variations. 

Some time after that we had arrived at the theatre, a jumble of sinister panels in dark timber, with rain-worn posters over the windows, stained with mould, and haunted by images of shows long since closed.

A short while later we came upon the video-arcade, a seizure of coloured lights in plastic cabinets, with a gum-plastered claw-machine guarding the entrance, stuffed with Pokemon, and crowned by the glowing yellow head of Pikachu.

Just before nightfall we came upon the cavern entrance, a dragon’s mouth of jagged rocks and yawning blackness, with gloomy trees on either side, smeared with ash, and obstructed by the piled bones of knights who had come before us.

Try a variation of your own. Make it funny and not gothic if you want.
Try another variation. Make it creepy and gothic.